diff --git a/lib/mcp_registry_web/components/layouts.ex b/lib/mcp_registry_web/components/layouts.ex
index fc8b11c..4ab8ece 100644
--- a/lib/mcp_registry_web/components/layouts.ex
+++ b/lib/mcp_registry_web/components/layouts.ex
@@ -38,6 +38,13 @@ defmodule McpRegistryWeb.Layouts do
     default: false,
     doc: "drop the reading-width cap, for the landing page's full-bleed sections"
 
+  attr :sponsors, :boolean,
+    default: false,
+    doc: """
+    put the content in a main column with the sponsor sidebar beside it. A page
+    with a sidebar of its own (a listing) keeps it, and uses the same hook.
+    """
+
   slot :rail,
     doc: """
     A full-width bar pinned under the site header — breadcrumbs on the left,
@@ -96,8 +103,18 @@ defmodule McpRegistryWeb.Layouts do
     </div>
 
     <main id="main" class={["px-4 pb-10 sm:px-6 lg:px-8", if(@rail != [], do: "pt-6", else: "pt-10")]}>
-      <div class={["mx-auto space-y-6", if(@wide, do: "max-w-6xl", else: "max-w-5xl")]}>
-        {render_slot(@inner_block)}
+      <div class={[
+        "mx-auto space-y-6",
+        if(@wide or @sponsors, do: "max-w-6xl", else: "max-w-5xl")
+      ]}>
+        <%= if @sponsors do %>
+          <div class="grid gap-8 lg:grid-cols-12">
+            <div class="min-w-0 space-y-6 lg:col-span-8">{render_slot(@inner_block)}</div>
+            <.sponsor_sidebar class="lg:col-span-4" />
+          </div>
+        <% else %>
+          {render_slot(@inner_block)}
+        <% end %>
       </div>
     </main>
 
@@ -227,7 +244,80 @@ defmodule McpRegistryWeb.Layouts do
   end
 
   @doc """
-  The sponsored block: four square slots, two up.
+  A right-hand sidebar that scrolls with the page and then holds, holding the
+  sponsored block below whatever the caller puts in it.
+
+  The sidebar is taller than the window -- five 250px tiles alone are -- so
+  pinning it by its top, the usual sticky sidebar, would show only its first
+  screenful until the main column ran out, sometimes 10,000 words later. The
+  `.StickySidebar` hook pins it by its bottom instead: it scrolls with the page
+  until its last item is in view, then stays.
+
+  ## Examples
+
+      <Layouts.sponsor_sidebar class="lg:col-span-4" />
+
+  A page with its own sidebar can use the behaviour without the component:
+  `phx-hook="McpRegistryWeb.Layouts.StickySidebar"`, plus
+  `phx-mounted={JS.ignore_attributes(["style"])}`.
+  """
+  attr :id, :string, default: "sponsor-sidebar"
+  attr :class, :any, default: nil
+  slot :inner_block
+
+  def sponsor_sidebar(assigns) do
+    ~H"""
+    <aside
+      id={@id}
+      phx-hook=".StickySidebar"
+      phx-mounted={JS.ignore_attributes(["style"])}
+      class={["min-w-0 space-y-6 self-start lg:sticky lg:top-32", @class]}
+    >
+      <script :type={Phoenix.LiveView.ColocatedHook} name=".StickySidebar">
+        // Sticky with a negative top: the browser scrolls the sidebar with the
+        // page until its bottom meets the bottom of the window, then holds it
+        // there. No scroll listener -- only a recalculation when the window or
+        // the sidebar changes size. The style it sets belongs to the browser;
+        // phx-mounted tells LiveView not to strip it on the next patch.
+        const PINNED_TOP = 128 // lg:top-32, clear of the header and rail
+        const GAP = 24 // breathing room under the last item
+
+        export default {
+          mounted() {
+            this.wide = window.matchMedia("(min-width: 1024px)")
+            this.update = () => {
+              // Below lg the sidebar stacks under the content; leave it be.
+              if (!this.wide.matches) return (this.el.style.top = "")
+              const height = this.el.offsetHeight
+              const fits = PINNED_TOP + height + GAP <= window.innerHeight
+              this.el.style.top = fits ? "" : `${window.innerHeight - height - GAP}px`
+            }
+            // Contents change height after load: images, tabs, a README.
+            this.observer = new ResizeObserver(this.update)
+            this.observer.observe(this.el)
+            window.addEventListener("resize", this.update)
+            this.wide.addEventListener("change", this.update)
+            this.update()
+          },
+          updated() {
+            this.update()
+          },
+          destroyed() {
+            this.observer.disconnect()
+            window.removeEventListener("resize", this.update)
+            this.wide.removeEventListener("change", this.update)
+          }
+        }
+      </script>
+      {render_slot(@inner_block)}
+      <.sponsors />
+    </aside>
+    """
+  end
+
+  @doc """
+  The sponsored block: five square slots, one per row -- the book first and
+  last, and the three slots for sale between.
 
   Lives here rather than in `CoreComponents` because it is site chrome: it
   belongs to the page frame, not to the listing being described, and any page
@@ -256,15 +346,22 @@ defmodule McpRegistryWeb.Layouts do
   @enquiry_subject "Interested Sponsor for MCP Harbor"
   @enquiry_body "I'm interested in bidding $____ for a Sponsor position on MCP Harbor."
 
+  @book_slot %{
+    file: "Book.png",
+    alt: "MCP Server Optimization — the book behind this registry",
+    kind: :book
+  }
+
+  # The book opens and closes the block. The sidebar is taller than the window
+  # and settles with its bottom in view, so the last tile is the one a reader
+  # keeps seeing for the rest of a long page -- and the first is the one they
+  # see before they scroll at all.
   @sponsor_slots [
-    %{
-      file: "Book.png",
-      alt: "MCP Server Optimization — the book behind this registry",
-      kind: :book
-    },
+    @book_slot,
     %{file: "sponsor-1.png", alt: "Sponsor slot available — email to enquire", kind: :enquiry},
     %{file: "sponsor-2.png", alt: "Sponsor slot available — email to enquire", kind: :enquiry},
-    %{file: "sponsor-3.png", alt: "Sponsor slot available — email to enquire", kind: :enquiry}
+    %{file: "sponsor-3.png", alt: "Sponsor slot available — email to enquire", kind: :enquiry},
+    @book_slot
   ]
 
   def sponsors(assigns) do
diff --git a/lib/mcp_registry_web/live/changelog_live.ex b/lib/mcp_registry_web/live/changelog_live.ex
index 8f39453..c64e23f 100644
--- a/lib/mcp_registry_web/live/changelog_live.ex
+++ b/lib/mcp_registry_web/live/changelog_live.ex
@@ -31,7 +31,7 @@ defmodule McpRegistryWeb.ChangelogLive do
   @impl true
   def render(assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers} wide={true}>
+    <Layouts.app flash={@flash} active={:servers} wide={true} sponsors={true}>
       <header class="rise space-y-3 border-b border-rule pb-6">
         <h1 class="text-2xl font-semibold tracking-tight text-balance sm:text-3xl">
           What changed in MCP servers
diff --git a/lib/mcp_registry_web/live/server_live/agent.ex b/lib/mcp_registry_web/live/server_live/agent.ex
index 98a6804..2020867 100644
--- a/lib/mcp_registry_web/live/server_live/agent.ex
+++ b/lib/mcp_registry_web/live/server_live/agent.ex
@@ -103,7 +103,7 @@ defmodule McpRegistryWeb.ServerLive.Agent do
   @impl true
   def render(assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers} wide={true}>
+    <Layouts.app flash={@flash} active={:servers} wide={true} sponsors={true}>
       <:rail>
         <nav aria-label="Breadcrumb" class="min-w-0 font-mono text-xs">
           <ol class="flex flex-wrap items-center gap-x-1.5 gap-y-1 text-dim">
diff --git a/lib/mcp_registry_web/live/server_live/capabilities.ex b/lib/mcp_registry_web/live/server_live/capabilities.ex
index 6a0f92f..39b7ad6 100644
--- a/lib/mcp_registry_web/live/server_live/capabilities.ex
+++ b/lib/mcp_registry_web/live/server_live/capabilities.ex
@@ -138,7 +138,7 @@ defmodule McpRegistryWeb.ServerLive.Capabilities do
   @impl true
   def render(assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers} wide={true}>
+    <Layouts.app flash={@flash} active={:servers} wide={true} sponsors={true}>
       <:rail>
         <.crumbs
           server={@server}
diff --git a/lib/mcp_registry_web/live/server_live/changelog.ex b/lib/mcp_registry_web/live/server_live/changelog.ex
index 66d829f..197b44c 100644
--- a/lib/mcp_registry_web/live/server_live/changelog.ex
+++ b/lib/mcp_registry_web/live/server_live/changelog.ex
@@ -58,7 +58,7 @@ defmodule McpRegistryWeb.ServerLive.Changelog do
   @impl true
   def render(assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers} wide={true}>
+    <Layouts.app flash={@flash} active={:servers} wide={true} sponsors={true}>
       <:rail>
         <nav aria-label="Breadcrumb" class="min-w-0 font-mono text-xs">
           <ol class="flex flex-wrap items-center gap-x-1.5 gap-y-1 text-dim">
diff --git a/lib/mcp_registry_web/live/server_live/home.ex b/lib/mcp_registry_web/live/server_live/home.ex
index a63d9e4..40da8e6 100644
--- a/lib/mcp_registry_web/live/server_live/home.ex
+++ b/lib/mcp_registry_web/live/server_live/home.ex
@@ -182,167 +182,178 @@ defmodule McpRegistryWeb.ServerLive.Home do
         </div>
       </section>
 
-      <section :if={@featured != []} aria-labelledby="featured-heading" class="space-y-5 pt-8">
-        <div class="flex flex-wrap items-end justify-between gap-x-6 gap-y-2">
-          <div class="space-y-1.5">
-            <p class="font-mono text-[11px] tracking-wide text-dim uppercase">
-              most recently updated
-            </p>
-            <h2
-              id="featured-heading"
-              class="text-xl font-semibold tracking-tight text-balance sm:text-2xl"
-            >
-              Servers to start with
-            </h2>
-          </div>
-          <.link
-            navigate={~p"/servers"}
-            class="group flex items-center gap-1.5 rounded-field px-1 py-1 font-mono text-xs text-dim transition-colors hover:text-ink"
-          >
-            all {format_number(@stats.servers)}
-            <.icon
-              name="hero-arrow-right-micro"
-              class="size-3.5 transition-transform duration-200 group-hover:translate-x-0.5"
-            />
-          </.link>
-        </div>
-
-        <ul class="grid gap-3 sm:grid-cols-2 lg:grid-cols-3">
-          <li :for={server <- @featured}>
-            <.link
-              navigate={server_path(server)}
-              class="group flex h-full flex-col gap-2 rounded-box border border-rule bg-surface/50 p-4 transition-all duration-200 hover:-translate-y-0.5 hover:border-rule-strong hover:bg-surface hover:shadow-md"
-            >
-              <div class="flex items-start gap-3">
-                <.server_logo server={server} size="size-8 text-[11px]" />
-
-                <div class="min-w-0 flex-1 space-y-1">
-                  <div class="flex items-start justify-between gap-3">
-                    <h3 class="font-medium tracking-tight text-balance transition-colors group-hover:text-brand">
-                      {server.title}
-                    </h3>
-                    <span class={[
-                      "shrink-0 rounded-full border px-2 py-0.5 font-mono text-[10px]",
-                      Layouts.transport_tone(server.transport)
-                    ]}>
-                      {server.transport}
-                    </span>
-                  </div>
-
-                  <p class="font-mono text-[11px] break-all text-dim">
-                    {Server.namespace(server)}{Server.short_name(server)}
-                  </p>
-                </div>
-              </div>
-
-              <p class="line-clamp-3 text-sm text-pretty text-dim">{server.description}</p>
-
-              <div class="mt-auto flex flex-wrap items-center gap-x-3 gap-y-1 pt-1 font-mono text-[11px] text-dim">
-                <span :if={server.tools != []}>{length(server.tools)} tools</span>
-                <span :for={tag <- Enum.take(server.tags, 2)}>#{tag}</span>
+      <%!-- The opening sections (hero, search, numbers, the MCP endpoint) are
+            designed full width; the sponsors join from here down, beside the
+            featured servers, rather than squeezing the hero into two thirds. --%>
+      <div class="grid gap-8 lg:grid-cols-12">
+        <div class="min-w-0 space-y-6 lg:col-span-8">
+          <section :if={@featured != []} aria-labelledby="featured-heading" class="space-y-5 pt-8">
+            <div class="flex flex-wrap items-end justify-between gap-x-6 gap-y-2">
+              <div class="space-y-1.5">
+                <p class="font-mono text-[11px] tracking-wide text-dim uppercase">
+                  most recently updated
+                </p>
+                <h2
+                  id="featured-heading"
+                  class="text-xl font-semibold tracking-tight text-balance sm:text-2xl"
+                >
+                  Servers to start with
+                </h2>
               </div>
-            </.link>
-          </li>
-        </ul>
-      </section>
+              <.link
+                navigate={~p"/servers"}
+                class="group flex items-center gap-1.5 rounded-field px-1 py-1 font-mono text-xs text-dim transition-colors hover:text-ink"
+              >
+                all {format_number(@stats.servers)}
+                <.icon
+                  name="hero-arrow-right-micro"
+                  class="size-3.5 transition-transform duration-200 group-hover:translate-x-0.5"
+                />
+              </.link>
+            </div>
 
-      <section aria-labelledby="how-heading" class="space-y-5 pt-8">
-        <div class="space-y-1.5">
-          <p class="font-mono text-[11px] tracking-wide text-dim uppercase">how it works</p>
-          <h2 id="how-heading" class="text-xl font-semibold tracking-tight text-balance sm:text-2xl">
-            From search to tool call
-          </h2>
-        </div>
+            <ul class="grid gap-3 sm:grid-cols-2 lg:grid-cols-3">
+              <li :for={server <- @featured}>
+                <.link
+                  navigate={server_path(server)}
+                  class="group flex h-full flex-col gap-2 rounded-box border border-rule bg-surface/50 p-4 transition-all duration-200 hover:-translate-y-0.5 hover:border-rule-strong hover:bg-surface hover:shadow-md"
+                >
+                  <div class="flex items-start gap-3">
+                    <.server_logo server={server} size="size-8 text-[11px]" />
+
+                    <div class="min-w-0 flex-1 space-y-1">
+                      <div class="flex items-start justify-between gap-3">
+                        <h3 class="font-medium tracking-tight text-balance transition-colors group-hover:text-brand">
+                          {server.title}
+                        </h3>
+                        <span class={[
+                          "shrink-0 rounded-full border px-2 py-0.5 font-mono text-[10px]",
+                          Layouts.transport_tone(server.transport)
+                        ]}>
+                          {server.transport}
+                        </span>
+                      </div>
+
+                      <p class="font-mono text-[11px] break-all text-dim">
+                        {Server.namespace(server)}{Server.short_name(server)}
+                      </p>
+                    </div>
+                  </div>
 
-        <ol class="grid gap-px overflow-hidden rounded-box border border-rule bg-rule sm:grid-cols-3">
-          <.step index="01" label="find" icon="hero-magnifying-glass">
-            Search by name, transport or tool name. Every listing shows what it exposes and what it
-            needs before you install anything.
-          </.step>
-          <.step index="02" label="install" icon="hero-command-line">
-            Each page carries the package identifier or remote URL, the environment variables the
-            server expects, and a command you can copy.
-          </.step>
-          <.step index="03" label="call" icon="hero-bolt">
-            Your client discovers the tools on connect. Or skip the browser entirely and let your
-            agent query this registry through its MCP endpoint.
-          </.step>
-        </ol>
-      </section>
+                  <p class="line-clamp-3 text-sm text-pretty text-dim">{server.description}</p>
 
-      <section aria-labelledby="subscribe-heading" class="pt-8">
-        <div class="rounded-box border border-rule bg-surface/60 p-5 sm:p-7">
-          <div class="flex flex-col gap-6 sm:flex-row sm:items-start sm:justify-between">
-            <div class="max-w-md space-y-2">
-              <p class="flex items-center gap-2 font-mono text-[11px] tracking-wide text-dim uppercase">
-                <.icon name="hero-envelope" class="size-3.5 text-brand" /> the short list
-              </p>
+                  <div class="mt-auto flex flex-wrap items-center gap-x-3 gap-y-1 pt-1 font-mono text-[11px] text-dim">
+                    <span :if={server.tools != []}>{length(server.tools)} tools</span>
+                    <span :for={tag <- Enum.take(server.tags, 2)}>#{tag}</span>
+                  </div>
+                </.link>
+              </li>
+            </ul>
+          </section>
+
+          <section aria-labelledby="how-heading" class="space-y-5 pt-8">
+            <div class="space-y-1.5">
+              <p class="font-mono text-[11px] tracking-wide text-dim uppercase">how it works</p>
               <h2
-                id="subscribe-heading"
+                id="how-heading"
                 class="text-xl font-semibold tracking-tight text-balance sm:text-2xl"
               >
-                New and notable MCP servers
+                From search to tool call
               </h2>
-              <p class="text-sm text-pretty text-dim">
-                One email when enough has landed to be worth reading — roughly monthly, sometimes
-                less. New listings and notable updates, nothing else. Your address is not shared,
-                and every email carries an unsubscribe link.
-              </p>
             </div>
 
-            <div class="w-full sm:max-w-xs">
-              <p
-                :if={@subscribed?}
-                role="status"
-                class="rise flex items-center gap-2 rounded-field border border-success/40 bg-canvas px-3 py-2.5 text-sm"
-              >
-                <.icon name="hero-check-circle" class="size-4 shrink-0 text-success" />
-                You're on the list.
-              </p>
-
-              <.form
-                :if={!@subscribed?}
-                for={@form}
-                id="subscribe-form"
-                phx-submit="subscribe"
-                class="flex flex-col gap-2 sm:flex-row sm:items-start"
-              >
-                <div class="min-w-0 flex-1">
-                  <.input
-                    field={@form[:email]}
-                    type="email"
-                    placeholder="you@example.com"
-                    autocomplete="email"
-                    aria-label="Email address"
-                    required
-                  />
+            <ol class="grid gap-px overflow-hidden rounded-box border border-rule bg-rule sm:grid-cols-3">
+              <.step index="01" label="find" icon="hero-magnifying-glass">
+                Search by name, transport or tool name. Every listing shows what it exposes and what it
+                needs before you install anything.
+              </.step>
+              <.step index="02" label="install" icon="hero-command-line">
+                Each page carries the package identifier or remote URL, the environment variables the
+                server expects, and a command you can copy.
+              </.step>
+              <.step index="03" label="call" icon="hero-bolt">
+                Your client discovers the tools on connect. Or skip the browser entirely and let your
+                agent query this registry through its MCP endpoint.
+              </.step>
+            </ol>
+          </section>
+
+          <section aria-labelledby="subscribe-heading" class="pt-8">
+            <div class="rounded-box border border-rule bg-surface/60 p-5 sm:p-7">
+              <div class="flex flex-col gap-6 sm:flex-row sm:items-start sm:justify-between">
+                <div class="max-w-md space-y-2">
+                  <p class="flex items-center gap-2 font-mono text-[11px] tracking-wide text-dim uppercase">
+                    <.icon name="hero-envelope" class="size-3.5 text-brand" /> the short list
+                  </p>
+                  <h2
+                    id="subscribe-heading"
+                    class="text-xl font-semibold tracking-tight text-balance sm:text-2xl"
+                  >
+                    New and notable MCP servers
+                  </h2>
+                  <p class="text-sm text-pretty text-dim">
+                    One email when enough has landed to be worth reading — roughly monthly, sometimes
+                    less. New listings and notable updates, nothing else. Your address is not shared,
+                    and every email carries an unsubscribe link.
+                  </p>
                 </div>
-                <.button variant="primary" type="submit" phx-disable-with="Adding…">
-                  Subscribe
-                </.button>
-              </.form>
-            </div>
-          </div>
-        </div>
-      </section>
 
-      <section aria-labelledby="cta-heading" class="pt-8">
-        <div class="flex flex-col items-start gap-5 rounded-box border border-rule bg-sunken/70 p-5 sm:flex-row sm:items-center sm:justify-between sm:p-7">
-          <div class="space-y-1.5">
-            <h2 id="cta-heading" class="text-lg font-semibold tracking-tight text-balance">
-              Start browsing, or add what is missing
-            </h2>
-            <p class="max-w-md text-sm text-pretty text-dim">
-              Listings are free and stay free. Submissions go live after a quick review, and agents
-              can submit through the API without a browser.
-            </p>
-          </div>
-          <div class="flex flex-wrap gap-2">
-            <.button variant="primary" navigate={~p"/servers"}>Browse the catalogue</.button>
-            <.button variant="soft" navigate={~p"/submit"}>Submit a server</.button>
-          </div>
+                <div class="w-full sm:max-w-xs">
+                  <p
+                    :if={@subscribed?}
+                    role="status"
+                    class="rise flex items-center gap-2 rounded-field border border-success/40 bg-canvas px-3 py-2.5 text-sm"
+                  >
+                    <.icon name="hero-check-circle" class="size-4 shrink-0 text-success" />
+                    You're on the list.
+                  </p>
+
+                  <.form
+                    :if={!@subscribed?}
+                    for={@form}
+                    id="subscribe-form"
+                    phx-submit="subscribe"
+                    class="flex flex-col gap-2 sm:flex-row sm:items-start"
+                  >
+                    <div class="min-w-0 flex-1">
+                      <.input
+                        field={@form[:email]}
+                        type="email"
+                        placeholder="you@example.com"
+                        autocomplete="email"
+                        aria-label="Email address"
+                        required
+                      />
+                    </div>
+                    <.button variant="primary" type="submit" phx-disable-with="Adding…">
+                      Subscribe
+                    </.button>
+                  </.form>
+                </div>
+              </div>
+            </div>
+          </section>
+
+          <section aria-labelledby="cta-heading" class="pt-8">
+            <div class="flex flex-col items-start gap-5 rounded-box border border-rule bg-sunken/70 p-5 sm:flex-row sm:items-center sm:justify-between sm:p-7">
+              <div class="space-y-1.5">
+                <h2 id="cta-heading" class="text-lg font-semibold tracking-tight text-balance">
+                  Start browsing, or add what is missing
+                </h2>
+                <p class="max-w-md text-sm text-pretty text-dim">
+                  Listings are free and stay free. Submissions go live after a quick review, and agents
+                  can submit through the API without a browser.
+                </p>
+              </div>
+              <div class="flex flex-wrap gap-2">
+                <.button variant="primary" navigate={~p"/servers"}>Browse the catalogue</.button>
+                <.button variant="soft" navigate={~p"/submit"}>Submit a server</.button>
+              </div>
+            </div>
+          </section>
         </div>
-      </section>
+        <Layouts.sponsor_sidebar class="lg:col-span-4 lg:mt-8" />
+      </div>
     </Layouts.app>
     """
   end
diff --git a/lib/mcp_registry_web/live/server_live/index.ex b/lib/mcp_registry_web/live/server_live/index.ex
index e65fb9c..8de942e 100644
--- a/lib/mcp_registry_web/live/server_live/index.ex
+++ b/lib/mcp_registry_web/live/server_live/index.ex
@@ -69,7 +69,7 @@ defmodule McpRegistryWeb.ServerLive.Index do
   @impl true
   def render(assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers}>
+    <Layouts.app flash={@flash} active={:servers} sponsors={true}>
       <div class="rise">
         <.header>
           Browse MCP servers
diff --git a/lib/mcp_registry_web/live/server_live/new.ex b/lib/mcp_registry_web/live/server_live/new.ex
index ae24328..4535071 100644
--- a/lib/mcp_registry_web/live/server_live/new.ex
+++ b/lib/mcp_registry_web/live/server_live/new.ex
@@ -51,7 +51,7 @@ defmodule McpRegistryWeb.ServerLive.New do
   @impl true
   def render(assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:submit}>
+    <Layouts.app flash={@flash} active={:submit} sponsors={true}>
       <.header>
         Submit an MCP server
         <:subtitle>
diff --git a/lib/mcp_registry_web/live/server_live/show.ex b/lib/mcp_registry_web/live/server_live/show.ex
index d84ae28..7d2e235 100644
--- a/lib/mcp_registry_web/live/server_live/show.ex
+++ b/lib/mcp_registry_web/live/server_live/show.ex
@@ -523,50 +523,15 @@ defmodule McpRegistryWeb.ServerLive.Show do
 
         <%!-- Taller than the screen, so pinning it by its top hid everything below
               the first screenful -- the sponsors included -- until the main column
-              ran out, often 10,000 words later. .StickyAside pins it by its bottom
-              instead: it scrolls with the page until its last panel is in view,
-              then stays. The style it sets is the client's, so patches keep it. --%>
+              ran out, often 10,000 words later. The StickySidebar hook pins it by its bottom
+              instead (the hook lives with Layouts.sponsor_sidebar): it scrolls with
+              the page until its last panel is in view, then stays. --%>
         <aside
           id="listing-aside"
-          phx-hook=".StickyAside"
+          phx-hook="McpRegistryWeb.Layouts.StickySidebar"
           phx-mounted={JS.ignore_attributes(["style"])}
           class="min-w-0 space-y-6 self-start lg:sticky lg:top-32 lg:col-span-4"
         >
-          <script :type={Phoenix.LiveView.ColocatedHook} name=".StickyAside">
-            // Sticky with a negative top: the browser scrolls the sidebar with
-            // the page until its bottom meets the bottom of the window, then
-            // holds it there. No scroll listener -- only a recalculation when
-            // the window or the sidebar changes size.
-            const PINNED_TOP = 128 // lg:top-32, clear of the header and rail
-            const GAP = 24 // breathing room under the last panel
-
-            export default {
-              mounted() {
-                this.wide = window.matchMedia("(min-width: 1024px)")
-                this.update = () => {
-                  // Below lg the sidebar stacks under the content; leave it be.
-                  if (!this.wide.matches) return (this.el.style.top = "")
-                  const height = this.el.offsetHeight
-                  const fits = PINNED_TOP + height + GAP <= window.innerHeight
-                  this.el.style.top = fits ? "" : `${window.innerHeight - height - GAP}px`
-                }
-                // Panels change height after load (README, tabs, secrets).
-                this.observer = new ResizeObserver(this.update)
-                this.observer.observe(this.el)
-                window.addEventListener("resize", this.update)
-                this.wide.addEventListener("change", this.update)
-                this.update()
-              },
-              updated() {
-                this.update()
-              },
-              destroyed() {
-                this.observer.disconnect()
-                window.removeEventListener("resize", this.update)
-                this.wide.removeEventListener("change", this.update)
-              }
-            }
-          </script>
           <.panel
             :if={@server.env_vars != []}
             title="Secrets and scopes"
diff --git a/lib/mcp_registry_web/live/server_live/tools.ex b/lib/mcp_registry_web/live/server_live/tools.ex
index 42888a9..9305298 100644
--- a/lib/mcp_registry_web/live/server_live/tools.ex
+++ b/lib/mcp_registry_web/live/server_live/tools.ex
@@ -128,7 +128,7 @@ defmodule McpRegistryWeb.ServerLive.Tools do
   @impl true
   def render(%{live_action: :index} = assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers} wide={true}>
+    <Layouts.app flash={@flash} active={:servers} wide={true} sponsors={true}>
       <:rail><.crumbs server={@server} namespace={@namespace} short_name={@short_name} /></:rail>
 
       <header class="rise space-y-3 border-b border-rule pb-6">
@@ -164,7 +164,7 @@ defmodule McpRegistryWeb.ServerLive.Tools do
 
   def render(%{live_action: :show} = assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers} wide={true}>
+    <Layouts.app flash={@flash} active={:servers} wide={true} sponsors={true}>
       <:rail>
         <.crumbs server={@server} namespace={@namespace} short_name={@short_name} tool={@tool} />
       </:rail>
@@ -225,7 +225,7 @@ defmodule McpRegistryWeb.ServerLive.Tools do
 
   def render(%{live_action: :client} = assigns) do
     ~H"""
-    <Layouts.app flash={@flash} active={:servers} wide={true}>
+    <Layouts.app flash={@flash} active={:servers} wide={true} sponsors={true}>
       <:rail>
         <.crumbs
           server={@server}
diff --git a/test/mcp_registry_web/live/server_live_test.exs b/test/mcp_registry_web/live/server_live_test.exs
index 4ac67dc..08afc01 100644
--- a/test/mcp_registry_web/live/server_live_test.exs
+++ b/test/mcp_registry_web/live/server_live_test.exs
@@ -88,7 +88,7 @@ defmodule McpRegistryWeb.ServerLiveTest do
 
     # The hook scrolls the sidebar with the page until its last panel shows,
     # so the sponsors are reached early rather than at the end of the page.
-    assert aside =~ ~s(phx-hook="McpRegistryWeb.ServerLive.Show.StickyAside")
+    assert aside =~ ~s(phx-hook="McpRegistryWeb.Layouts.StickySidebar")
     # It sets `style` from the browser; a patch must not strip it.
     assert aside =~ "ignore_attrs"
     assert aside =~ "sponsors-heading"
diff --git a/test/mcp_registry_web/live/sponsor_sidebar_test.exs b/test/mcp_registry_web/live/sponsor_sidebar_test.exs
new file mode 100644
index 0000000..3d92f41
--- /dev/null
+++ b/test/mcp_registry_web/live/sponsor_sidebar_test.exs
@@ -0,0 +1,70 @@
+defmodule McpRegistryWeb.SponsorSidebarTest do
+  use McpRegistryWeb.ConnCase, async: true
+
+  import Phoenix.LiveViewTest
+  import McpRegistry.RegistryFixtures
+
+  alias McpRegistry.Changes.Change
+  alias McpRegistry.Repo
+
+  # Tile image sources in the order they render.
+  defp tiles(html) do
+    ~r{<img src="/images/(Book|sponsor-\d)[^"]*"}
+    |> Regex.scan(html)
+    |> Enum.map(&List.last/1)
+  end
+
+  test "the book opens and closes the block, with the three slots between", %{conn: conn} do
+    {:ok, _view, html} = live(conn, "/servers")
+    assert tiles(html) == ["Book", "sponsor-1", "sponsor-2", "sponsor-3", "Book"]
+  end
+
+  test "every page type carries the sponsor sidebar", %{conn: conn} do
+    server =
+      server_fixture(%{
+        title: "Weather",
+        tools: ~w(get_forecast),
+        prompts: ~w(review_diff),
+        resources: ["file:///alerts.json"]
+      })
+
+    Repo.insert!(%Change{server_id: server.id, kind: "tools", source: "probe", added: ["x"]})
+    base = "/servers/#{server.name}"
+
+    pages = [
+      "/",
+      "/servers",
+      "/submit",
+      "/changelog",
+      base,
+      base <> "/for/cursor",
+      base <> "/tools",
+      base <> "/tools/get_forecast",
+      base <> "/tools/get_forecast/cursor",
+      base <> "/prompts",
+      base <> "/prompts/review-diff",
+      base <> "/prompts/review-diff/cursor",
+      base <> "/resources",
+      base <> "/resources/file-alerts-json",
+      base <> "/resources/file-alerts-json/cursor",
+      base <> "/changelog",
+      base <> "/changelog/tools"
+    ]
+
+    for path <- pages do
+      html = conn |> get(path) |> html_response(200)
+
+      assert html =~ "sponsors-heading", "#{path} has no sponsor block"
+
+      assert html =~ ~s(phx-hook="McpRegistryWeb.Layouts.StickySidebar"),
+             "#{path} sidebar not pinned"
+
+      assert tiles(html) == ["Book", "sponsor-1", "sponsor-2", "sponsor-3", "Book"], path
+    end
+  end
+
+  test "the book's own page does not advertise itself", %{conn: conn} do
+    html = conn |> get("/book") |> html_response(200)
+    refute html =~ "sponsors-heading"
+  end
+end