diff --git a/src/app/api/v1/document-templates/[id]/generate-and-sign/route.ts b/src/app/api/v1/document-templates/[id]/generate-and-sign/route.ts
index af34db21..854a73e7 100644
--- a/src/app/api/v1/document-templates/[id]/generate-and-sign/route.ts
+++ b/src/app/api/v1/document-templates/[id]/generate-and-sign/route.ts
@@ -26,7 +26,11 @@ export const POST = withAuth(
           ipAddress: ctx.ipAddress,
           userAgent: ctx.userAgent,
         },
-        { dimensionUnit: body.dimensionUnit, overrides: body.overrides },
+        {
+          dimensionUnit: body.dimensionUnit,
+          overrides: body.overrides,
+          includeYachtDetails: body.includeYachtDetails,
+        },
       );
       return NextResponse.json({ data: result }, { status: 201 });
     } catch (error) {
diff --git a/src/components/documents/eoi-generate-dialog.tsx b/src/components/documents/eoi-generate-dialog.tsx
index 2d617277..870f22d2 100644
--- a/src/components/documents/eoi-generate-dialog.tsx
+++ b/src/components/documents/eoi-generate-dialog.tsx
@@ -191,6 +191,13 @@ export function EoiGenerateDialog({
   const [addressOverride, setAddressOverride] = useState<AddressOverrideState | null>(null);
   // Phase 3c - yacht spawn flow.
   const [yachtSpawnOpen, setYachtSpawnOpen] = useState(false);
+  // Section 3 (yacht details) inclusion toggle. Defaults to ON; the toggle
+  // only renders when a yacht is actually linked (no toggle = always ON,
+  // which matches today's behaviour). Set OFF to blank yacht.* + owner.*
+  // merge fields on the generated PDF even though the yacht record exists
+  // (early-stage clients, multi-berth deals where yacht-dims don't apply,
+  // explicit client request to keep Section 3 off the document).
+  const [includeYachtDetails, setIncludeYachtDetails] = useState(true);
 
   // Resolved EOI context - the actual values the document will be
   // auto-filled with. Loaded only while the dialog is open so we don't
@@ -564,6 +571,9 @@ export function EoiGenerateDialog({
           // the yacht's own `lengthUnit` column when unspecified.
           dimensionUnit: effectiveDimensionUnit,
           ...(hasAnyOverride ? { overrides } : {}),
+          // Only send the flag when the rep explicitly opted out; default
+          // (toggle ON) keeps existing behaviour without bloating the body.
+          ...(ctx?.yacht && !includeYachtDetails ? { includeYachtDetails: false } : {}),
         },
       });
       // Bounce every cache that surfaces the interest's EOI state so the
@@ -679,41 +689,60 @@ export function EoiGenerateDialog({
                 </dl>
               </div>
               <div className="space-y-1 border-t pt-2">
-                <div className="flex items-center justify-between">
+                <div className="flex items-center justify-between gap-2">
                   <p className="text-[10px] font-semibold uppercase tracking-wide text-muted-foreground">
-                    Optional (Section 3 - left blank if absent)
+                    Section 3 - yacht details
                   </p>
-                  {ctx.yacht ? (
-                    <div className="inline-flex rounded-md border bg-muted/30 p-0.5 text-[11px]">
-                      <button
-                        type="button"
-                        onClick={() => setDimensionUnit('ft')}
-                        className={
-                          'rounded px-2 py-0.5 transition-colors ' +
-                          (effectiveDimensionUnit === 'ft'
-                            ? 'bg-background font-medium shadow-sm'
-                            : 'text-muted-foreground hover:text-foreground')
-                        }
-                        aria-pressed={effectiveDimensionUnit === 'ft'}
-                      >
-                        ft
-                      </button>
-                      <button
-                        type="button"
-                        onClick={() => setDimensionUnit('m')}
-                        className={
-                          'rounded px-2 py-0.5 transition-colors ' +
-                          (effectiveDimensionUnit === 'm'
-                            ? 'bg-background font-medium shadow-sm'
-                            : 'text-muted-foreground hover:text-foreground')
-                        }
-                        aria-pressed={effectiveDimensionUnit === 'm'}
-                      >
-                        m
-                      </button>
-                    </div>
-                  ) : null}
+                  <div className="flex items-center gap-2">
+                    {ctx.yacht ? (
+                      <label className="inline-flex cursor-pointer items-center gap-1.5 text-[11px] text-muted-foreground">
+                        <input
+                          type="checkbox"
+                          checked={includeYachtDetails}
+                          onChange={(e) => setIncludeYachtDetails(e.target.checked)}
+                          className="h-3.5 w-3.5 cursor-pointer accent-primary"
+                          aria-label="Include yacht details on the EOI"
+                        />
+                        <span>Include on EOI</span>
+                      </label>
+                    ) : null}
+                    {ctx.yacht && includeYachtDetails ? (
+                      <div className="inline-flex rounded-md border bg-muted/30 p-0.5 text-[11px]">
+                        <button
+                          type="button"
+                          onClick={() => setDimensionUnit('ft')}
+                          className={
+                            'rounded px-2 py-0.5 transition-colors ' +
+                            (effectiveDimensionUnit === 'ft'
+                              ? 'bg-background font-medium shadow-sm'
+                              : 'text-muted-foreground hover:text-foreground')
+                          }
+                          aria-pressed={effectiveDimensionUnit === 'ft'}
+                        >
+                          ft
+                        </button>
+                        <button
+                          type="button"
+                          onClick={() => setDimensionUnit('m')}
+                          className={
+                            'rounded px-2 py-0.5 transition-colors ' +
+                            (effectiveDimensionUnit === 'm'
+                              ? 'bg-background font-medium shadow-sm'
+                              : 'text-muted-foreground hover:text-foreground')
+                          }
+                          aria-pressed={effectiveDimensionUnit === 'm'}
+                        >
+                          m
+                        </button>
+                      </div>
+                    ) : null}
+                  </div>
                 </div>
+                {ctx.yacht && !includeYachtDetails ? (
+                  <p className="text-[11px] text-muted-foreground">
+                    Yacht details will be omitted from the EOI even though a yacht is linked.
+                  </p>
+                ) : null}
                 <dl className="space-y-1.5">
                   <div className="flex items-start gap-2">
                     <div className="flex-1">
diff --git a/src/lib/services/document-templates.ts b/src/lib/services/document-templates.ts
index cb65221c..6f850a66 100644
--- a/src/lib/services/document-templates.ts
+++ b/src/lib/services/document-templates.ts
@@ -490,7 +490,7 @@ async function generateEoiFromSourcePdf(
   portId: string,
   context: GenerateInput,
   meta: AuditMeta,
-  options?: { dimensionUnit?: 'ft' | 'm' },
+  options?: { dimensionUnit?: 'ft' | 'm'; includeYachtDetails?: boolean },
   applied: AppliedOverrides = { resolved: {}, documentOverrideColumns: {} },
 ): Promise<{ document: DbDocument; file: DbFile }> {
   if (!context.interestId) {
@@ -501,6 +501,12 @@ async function generateEoiFromSourcePdf(
     await buildEoiContext(context.interestId, portId),
     applied,
   );
+  // Rep opted out of Section 3 — blank the yacht slot so the AcroForm fill
+  // skips writing the yacht.* / owner.* fields (matching the Documenso
+  // pathway).
+  if (options?.includeYachtDetails === false) {
+    eoiContext.yacht = null;
+  }
   const pdfBytes = await generateEoiPdfFromTemplate(eoiContext, {
     dimensionUnit: options?.dimensionUnit ?? eoiContext.yacht?.lengthUnit ?? 'ft',
   });
@@ -597,7 +603,14 @@ export async function generateAndSign(
   signers: GenerateAndSignInput['signers'],
   pathway: 'inapp' | 'documenso-template',
   meta: AuditMeta,
-  options?: { dimensionUnit?: 'ft' | 'm'; overrides?: EoiOverridesInput },
+  options?: {
+    dimensionUnit?: 'ft' | 'm';
+    overrides?: EoiOverridesInput;
+    /** False = blank out Section 3 (yacht.* + owner.* merge fields) even
+     *  when the interest carries a linked yacht. True (or unset) keeps the
+     *  current behaviour (auto-fill from yacht record). */
+    includeYachtDetails?: boolean;
+  },
 ) {
   // Phase 3b - apply per-field overrides BEFORE either pathway resolves the
   // EOI context, so any setAsDefault contact promotion is visible to the
@@ -623,7 +636,7 @@ async function generateAndSignViaInApp(
   context: GenerateInput,
   signers: GenerateAndSignInput['signers'],
   meta: AuditMeta,
-  options?: { dimensionUnit?: 'ft' | 'm' },
+  options?: { dimensionUnit?: 'ft' | 'm'; includeYachtDetails?: boolean },
   applied: AppliedOverrides = { resolved: {}, documentOverrideColumns: {} },
 ) {
   const template = await getTemplateById(templateId, portId);
@@ -755,7 +768,7 @@ async function generateAndSignViaDocumensoTemplate(
   portId: string,
   context: GenerateInput,
   meta: AuditMeta,
-  options?: { dimensionUnit?: 'ft' | 'm' },
+  options?: { dimensionUnit?: 'ft' | 'm'; includeYachtDetails?: boolean },
   applied: AppliedOverrides = { resolved: {}, documentOverrideColumns: {} },
 ) {
   if (!context.interestId) {
@@ -766,6 +779,14 @@ async function generateAndSignViaDocumensoTemplate(
     await buildEoiContext(context.interestId, portId),
     applied,
   );
+  // Rep opted out of Section 3 (yacht details) — blank the yacht slot so
+  // buildDocumensoPayload + the EOI template see "no yacht linked" and
+  // leave yacht.* / owner.* merge fields empty. Persisted in document
+  // metadata below for audit (kind: 'eoi_include_yacht_details=false').
+  const yachtDeclined = options?.includeYachtDetails === false;
+  if (yachtDeclined) {
+    eoiContext.yacht = null;
+  }
   const signers = await getPortEoiSigners(portId);
   // Per-port Documenso template + recipient IDs (with env fallback). Each
   // tenant pointing at its own Documenso instance has different numeric
@@ -908,6 +929,10 @@ async function generateAndSignViaDocumensoTemplate(
       pathway: 'documenso-template',
       templateId: env.DOCUMENSO_TEMPLATE_ID_EOI,
       interestId: context.interestId,
+      // Rep's explicit Section-3 choice. Audit-only — Docs row has no
+      // metadata jsonb; the blanked yacht.* / owner.* merge fields on the
+      // generated PDF are the user-visible evidence.
+      includeYachtDetails: !yachtDeclined,
     },
     ipAddress: meta.ipAddress,
     userAgent: meta.userAgent,
diff --git a/src/lib/validators/document-templates.ts b/src/lib/validators/document-templates.ts
index 7810b8be..eeb22e01 100644
--- a/src/lib/validators/document-templates.ts
+++ b/src/lib/validators/document-templates.ts
@@ -109,6 +109,14 @@ export const generateAndSignSchema = generateSchema.extend({
    *  EOI's Length/Width/Draft formValues. The drawer's toggle drives this;
    *  server defaults to the yacht's `lengthUnit` column when omitted. */
   dimensionUnit: z.enum(['ft', 'm']).optional(),
+  /** Optional Section 3 (yacht details) inclusion. Defaults to true when a
+   *  yacht is linked. Rep can flip OFF in the dialog to blank out yacht.*
+   *  + owner.* merge fields even though a yacht is on file — used when the
+   *  yacht is a placeholder, multi-berth deals where yacht-specific dims
+   *  don't apply, or the client explicitly asked for the section to stay
+   *  off the document. Persisted in `documents.metadata.includeYachtDetails`
+   *  for audit. */
+  includeYachtDetails: z.boolean().optional(),
   /** Phase 3b/3-follow-up - optional per-field overrides applied at generation. */
   overrides: z
     .object({