diff --git a/src/components/clinical-dashboard/ClinicalSidebar.tsx b/src/components/clinical-dashboard/ClinicalSidebar.tsx
index 73c2c298a..5d9966ec2 100644
--- a/src/components/clinical-dashboard/ClinicalSidebar.tsx
+++ b/src/components/clinical-dashboard/ClinicalSidebar.tsx
@@ -936,14 +936,14 @@ function ClinicalCollapsedRail({
       <div className="grid w-full shrink-0 justify-items-center gap-2 px-3">
         {collapseLocked ? (
           <span className={collapsedSidebarButton} aria-hidden="true">
-            <BrandMark tone="emphasis" className="h-7 w-7" />
+            <BrandMark tone="emphasis" optical="chrome" className="h-7 w-7" />
           </span>
         ) : (
           <>
             {/* Tablet: the expanded panel does not exist below lg, so show a
                 static brand mark instead of a dead expand control. */}
             <span className={cn("hidden md:grid lg:hidden", collapsedSidebarControl)} aria-hidden="true">
-              <BrandMark tone="emphasis" className="h-7 w-7" />
+              <BrandMark tone="emphasis" optical="chrome" className="h-7 w-7" />
             </span>
             <Button
               variant="ghost"
@@ -952,7 +952,11 @@ function ClinicalCollapsedRail({
               title="Expand sidebar"
               onClick={() => onCollapsedChange(false)}
             >
-              <BrandMark tone="emphasis" className="h-7 w-7 group-hover:hidden group-focus-visible:hidden" />
+              <BrandMark
+                tone="emphasis"
+                optical="chrome"
+                className="h-7 w-7 group-hover:hidden group-focus-visible:hidden"
+              />
               <PanelLeftOpen
                 aria-hidden="true"
                 className="hidden size-icon-lg group-hover:block group-focus-visible:block"
@@ -1188,7 +1192,7 @@ export function ClinicalMobileSidebar({
       closeLabel="Close Clinical Guide menu"
       placement="left"
       contentClassName={hiddenFrom === "lg" ? "lg:hidden" : "md:hidden"}
-      headerLeading={<BrandMark tone="emphasis" className="h-7 w-7 sm:h-8 sm:w-8" />}
+      headerLeading={<BrandMark tone="emphasis" optical="chrome" className="h-7 w-7 sm:h-8 sm:w-8" />}
       headerClassName={drawerHeader}
       titleClassName={drawerHeaderTitle}
       closeButtonClassName={drawerHeaderClose}
diff --git a/src/components/clinical-dashboard/account-setup-dialog.tsx b/src/components/clinical-dashboard/account-setup-dialog.tsx
index 366d690b8..7bff4bfb2 100644
--- a/src/components/clinical-dashboard/account-setup-dialog.tsx
+++ b/src/components/clinical-dashboard/account-setup-dialog.tsx
@@ -214,7 +214,7 @@ function AccountOrientationPanel() {
           data-testid="account-workspace-mark"
           className="grid size-tap place-items-center rounded-xl border border-[color:var(--border-lux)] bg-[color:var(--surface)] shadow-[var(--e2),var(--shadow-inset)]"
         >
-          <BrandMark tone="emphasis" className="h-8 w-8" />
+          <BrandMark tone="emphasis" optical="chrome" className="h-8 w-8" />
         </span>
         <h3
           id="account-workspace-benefits"
diff --git a/src/components/clinical-dashboard/brand.tsx b/src/components/clinical-dashboard/brand.tsx
index 02cc2b1f8..77a49b182 100644
--- a/src/components/clinical-dashboard/brand.tsx
+++ b/src/components/clinical-dashboard/brand.tsx
@@ -1,11 +1,5 @@
 import { cn } from "@/components/ui-primitives";
-import {
-  BRAND_COUNTER_TRANSFORM,
-  BRAND_GLYPH_TRANSFORM_BARE,
-  BRAND_POINT,
-  BRAND_STROKE_PATH,
-  BRAND_VIEWBOX,
-} from "@/lib/brand-mark";
+import { BRAND_COUNTER_TRANSFORM, BRAND_VIEWBOX, brandMarkOptics } from "@/lib/brand-mark";
 
 /**
  * Site brand mark: the PsychSift S — two counter-turning strokes divided by one
@@ -47,7 +41,34 @@ const BRAND_MARK_INK: Record<BrandMarkTone, string> = {
   contrast: "var(--brand-mark-contrast)",
 };
 
-export function BrandMark({ className, tone = "resting" }: { className?: string; tone?: BrandMarkTone }) {
+/**
+ * Which optical cut of the glyph to draw. The mark is a construction, not a
+ * bitmap, so it does not simply get smaller — two pieces of its negative space
+ * close up before anything else does.
+ *
+ * - `display` — the primary construction. Correct above 32px.
+ * - `chrome` — the small-size cut, for 32px and below: a wider gap between the
+ *   strokes and the point slid out of its cradle. Both are the brand's own
+ *   committed geometry, not a redraw.
+ *
+ * Sized by className, so the component cannot measure itself and this cannot be
+ * inferred. State it at the call site, matched to the height you are setting.
+ */
+export type BrandMarkOptical = "display" | "chrome";
+
+export function BrandMark({
+  className,
+  tone = "resting",
+  optical = "display",
+}: {
+  className?: string;
+  tone?: BrandMarkTone;
+  optical?: BrandMarkOptical;
+}) {
+  // One call, so the stroke, the point and the centring transform can only be
+  // taken as a set — the brand doc is explicit that mixing one variant's point
+  // with the other's placement puts the glyph off-centre in its box.
+  const { transform, stroke, point } = brandMarkOptics(optical);
   return (
     <svg
       viewBox={BRAND_VIEWBOX}
@@ -56,10 +77,10 @@ export function BrandMark({ className, tone = "resting" }: { className?: string;
       focusable="false"
       className={cn("shrink-0", className)}
     >
-      <g transform={BRAND_GLYPH_TRANSFORM_BARE} fill={BRAND_MARK_INK[tone]}>
-        <path d={BRAND_STROKE_PATH} />
-        <path d={BRAND_STROKE_PATH} transform={BRAND_COUNTER_TRANSFORM} />
-        <circle cx={BRAND_POINT.cx} cy={BRAND_POINT.cy} r={BRAND_POINT.r} />
+      <g transform={transform} fill={BRAND_MARK_INK[tone]}>
+        <path d={stroke} />
+        <path d={stroke} transform={BRAND_COUNTER_TRANSFORM} />
+        <circle cx={point.cx} cy={point.cy} r={point.r} />
       </g>
     </svg>
   );
diff --git a/src/components/ward-management/ward-management-navigation.tsx b/src/components/ward-management/ward-management-navigation.tsx
index 6d5a0e9d7..c1756ff1b 100644
--- a/src/components/ward-management/ward-management-navigation.tsx
+++ b/src/components/ward-management/ward-management-navigation.tsx
@@ -84,7 +84,7 @@ export function ClinicalRail({ activeMode }: { activeMode?: WardMode } = {}) {
     <>
       <div className={sidebarStyles.phoneBar}>
         <Link href="/mockups/ward-flow" className={sidebarStyles.phoneBrand}>
-          <BrandMark tone="emphasis" className={sidebarStyles.brandGlyph} />
+          <BrandMark tone="emphasis" optical="chrome" className={sidebarStyles.brandGlyph} />
           <span className={sidebarStyles.phoneBrandName}>Ward Flow</span>
         </Link>
         <button
@@ -117,7 +117,7 @@ export function ClinicalRail({ activeMode }: { activeMode?: WardMode } = {}) {
         closeLabel="Close Ward Flow menu"
         placement="left"
         contentClassName={sidebarStyles.drawerHidden}
-        headerLeading={<BrandMark tone="emphasis" className={sidebarStyles.brandGlyph} />}
+        headerLeading={<BrandMark tone="emphasis" optical="chrome" className={sidebarStyles.brandGlyph} />}
       >
         <div className={sidebarStyles.drawerBody}>
           <WardSidebarContent activeMode={activeMode} showBrandRow={false} onNavigate={() => setMenuOpen(false)} />
diff --git a/src/components/ward-management/ward-sidebar-content.tsx b/src/components/ward-management/ward-sidebar-content.tsx
index 7be20044b..7a7ae82f5 100644
--- a/src/components/ward-management/ward-sidebar-content.tsx
+++ b/src/components/ward-management/ward-sidebar-content.tsx
@@ -56,7 +56,7 @@ export function WardSidebarNav({
       {showBrandRow ? (
         <div className={styles.brandRow}>
           <Link href="/mockups/ward-flow" className={styles.brandLink} onClick={onNavigate}>
-            <BrandMark tone="emphasis" className={styles.brandGlyph} />
+            <BrandMark tone="emphasis" optical="chrome" className={styles.brandGlyph} />
             <span className={styles.brandText}>
               <span className={styles.brandName}>Ward Flow</span>
               <span className={styles.brandTagline}>Synthetic patient-flow prototype</span>
diff --git a/src/lib/brand-mark.ts b/src/lib/brand-mark.ts
index 018321ee8..6ce01d93a 100644
--- a/src/lib/brand-mark.ts
+++ b/src/lib/brand-mark.ts
@@ -36,6 +36,56 @@ export const BRAND_GLYPH_TRANSFORM_SMALL = "translate(122.7103 51.2) scale(4.080
  *  mark therefore occupies exactly the slot the tiled version used to. */
 export const BRAND_GLYPH_TRANSFORM_BARE = "translate(114.8907 0) scale(5.1006)";
 
+/** The bare glyph's small-size placement — the counterpart of
+ *  BRAND_GLYPH_TRANSFORM_SMALL for the untiled, in-app mark.
+ *
+ *  Not a new measurement. The brand doc fixes the two ink boxes: the primary
+ *  glyph spans 0 to 55.33 horizontally, the small variant 0 to 65.33, and both
+ *  span the same 0 to 100.38 vertically. Every placement here centres that box
+ *  in the 512 viewBox, which is verifiable against the three transforms above —
+ *  each lands its centre on 256.000 to within 0.003, the rounding of a
+ *  two-decimal box figure.
+ *
+ *  Two consequences, and both are why this is a derivation rather than a redraw:
+ *
+ *  The vertical extent is identical between the variants (the point slides
+ *  sideways; its cy and r do not move), so the scale is unchanged at 5.1006 —
+ *  100.3813 x 5.1006 = 512.0, the bare variant's whole point.
+ *
+ *  The point moves exactly 10 units out and is the box's right edge, so the box
+ *  widens by exactly 10 and its centre by exactly 5. The placement therefore
+ *  shifts left by 5 glyph units at this scale: 114.8907 - 5 x 5.1006 = 89.3877.
+ *  The same arithmetic reproduces the committed tiled pair (143.1125 - 5 x
+ *  4.0804 = 122.7103, as shipped), which is the check that the rule is the one
+ *  actually used rather than one that merely fits.
+ *
+ *  It travels with BRAND_STROKE_PATH_SMALL and BRAND_POINT_SMALL as a set. The
+ *  doc is explicit that mixing one variant's point with the other's placement
+ *  puts the glyph off-centre; `brandMarkOptics()` below is the only supported
+ *  way to pick, so a caller cannot half-apply the variant. */
+export const BRAND_GLYPH_TRANSFORM_BARE_SMALL = "translate(89.3877 0) scale(5.1006)";
+
+/** The two optical variants of the bare glyph, as whole sets.
+ *
+ *  `display` is the primary construction. `chrome` is the small-size cut: the
+ *  4.2-unit gap between the strokes opened to 7.2, and the point slid 10 units
+ *  out of its cradle so the crescent opens from 7.26 to 11.55.
+ *
+ *  The threshold is 32px, from the brand doc's own "at 32 px and below two
+ *  things close up" - below it the cut and the crescent both fall under two
+ *  pixels and the dot fuses into the S, which reads as a heavy blob at the top
+ *  of a mark whose lower stroke is already the thinner one. That fusion is what
+ *  made the mark look top-heavy in app chrome; the deeper `--brand-mark-emphasis`
+ *  ink compensates for it, and this fixes it.
+ *
+ *  Below about 20px the crescent is under two pixels whatever is done. That is
+ *  the size, not the placement, and no variant rescues it. */
+export function brandMarkOptics(variant: "display" | "chrome") {
+  return variant === "chrome"
+    ? { transform: BRAND_GLYPH_TRANSFORM_BARE_SMALL, stroke: BRAND_STROKE_PATH_SMALL, point: BRAND_POINT_SMALL }
+    : { transform: BRAND_GLYPH_TRANSFORM_BARE, stroke: BRAND_STROKE_PATH, point: BRAND_POINT };
+}
+
 /** The upper stroke. Four arcs and the straight cut, meeting at two cusps. */
 export const BRAND_STROKE_PATH =
   "M41.3675 2.6554 A17.7232 17.7232 0 0 0 29.0679 28.0493 A13 13 0 0 1 28.8667 40.1963 " +
diff --git a/tests/brand-mark-optics.test.ts b/tests/brand-mark-optics.test.ts
new file mode 100644
index 000000000..4ecf8cb2d
--- /dev/null
+++ b/tests/brand-mark-optics.test.ts
@@ -0,0 +1,192 @@
+import { execFileSync } from "node:child_process";
+import { readFileSync } from "node:fs";
+import path from "node:path";
+
+import { describe, expect, it } from "vitest";
+
+import {
+  BRAND_GLYPH_TRANSFORM,
+  BRAND_GLYPH_TRANSFORM_BARE,
+  BRAND_GLYPH_TRANSFORM_BARE_SMALL,
+  BRAND_GLYPH_TRANSFORM_SMALL,
+  BRAND_POINT,
+  BRAND_POINT_SMALL,
+  BRAND_STROKE_PATH,
+  BRAND_STROKE_PATH_SMALL,
+  brandMarkOptics,
+} from "@/lib/brand-mark";
+
+/**
+ * The mark is a construction, not a bitmap, and it does not simply get smaller.
+ * Two pieces of its negative space — the 4.2-unit cut between the strokes and
+ * the 7.26-unit crescent around the point — close up at 32px and below, which
+ * fuses the dot into the S and reads as a heavy blob above an already-thinner
+ * lower stroke. That is the top-heavy look; `docs/brand/psychsift-logo.md`
+ * §"Small sizes" specifies a separate optical cut for exactly that range.
+ *
+ * These tests guard the two ways that can go wrong: the placement arithmetic,
+ * and a call site drawing the wrong cut for the size it renders at.
+ */
+
+/** Ink bounding boxes, from docs/brand/psychsift-logo.md. */
+const INK = { displayWidth: 55.33, chromeWidth: 65.33, height: 100.38 };
+const VIEWBOX = 512;
+/** Two-decimal box figures, so the centre lands within a rounding of 256. */
+const CENTRING_TOLERANCE = 0.01;
+
+function parseTransform(transform: string) {
+  const match = /^translate\((-?[\d.]+) (-?[\d.]+)\) scale\(([\d.]+)\)$/.exec(transform);
+  expect(match, `unparseable transform: ${transform}`).not.toBeNull();
+  const [, x, y, scale] = match as RegExpExecArray;
+  return { x: Number(x), y: Number(y), scale: Number(scale) };
+}
+
+describe("the glyph placements all centre their own ink box", () => {
+  it.each([
+    ["BRAND_GLYPH_TRANSFORM (tiled, display)", BRAND_GLYPH_TRANSFORM, INK.displayWidth],
+    ["BRAND_GLYPH_TRANSFORM_SMALL (tiled, chrome)", BRAND_GLYPH_TRANSFORM_SMALL, INK.chromeWidth],
+    ["BRAND_GLYPH_TRANSFORM_BARE (bare, display)", BRAND_GLYPH_TRANSFORM_BARE, INK.displayWidth],
+    ["BRAND_GLYPH_TRANSFORM_BARE_SMALL (bare, chrome)", BRAND_GLYPH_TRANSFORM_BARE_SMALL, INK.chromeWidth],
+  ])("%s lands its centre on 256", (_name, transform, inkWidth) => {
+    const { x, scale } = parseTransform(transform);
+    expect(x + (inkWidth / 2) * scale).toBeCloseTo(VIEWBOX / 2, 1);
+    expect(Math.abs(x + (inkWidth / 2) * scale - VIEWBOX / 2)).toBeLessThan(CENTRING_TOLERANCE * VIEWBOX);
+  });
+});
+
+describe("the bare pair is one construction at two cuts", () => {
+  const display = parseTransform(BRAND_GLYPH_TRANSFORM_BARE);
+  const chrome = parseTransform(BRAND_GLYPH_TRANSFORM_BARE_SMALL);
+
+  it("shares a scale, because only the point's x moves between variants", () => {
+    // BRAND_POINT_SMALL keeps cy and r, so the vertical extent is identical and
+    // the bare scale — which exists to fill the box top to bottom — cannot change.
+    expect(BRAND_POINT_SMALL.cy).toBe(BRAND_POINT.cy);
+    expect(BRAND_POINT_SMALL.r).toBe(BRAND_POINT.r);
+    expect(chrome.scale).toBe(display.scale);
+    expect(chrome.y).toBe(display.y);
+  });
+
+  it("fills the box top to bottom at that scale", () => {
+    expect(INK.height * display.scale).toBeCloseTo(VIEWBOX, 0);
+  });
+
+  it("shifts left by exactly half the point's travel", () => {
+    // The point moves 10 units out and is the box's right edge, so the box
+    // widens by 10 and its centre by 5.
+    const travel = BRAND_POINT_SMALL.cx - BRAND_POINT.cx;
+    expect(travel).toBe(10);
+    expect(INK.chromeWidth - INK.displayWidth).toBeCloseTo(travel, 1);
+    expect(display.x - chrome.x).toBeCloseTo((travel / 2) * display.scale, 2);
+  });
+
+  it("uses the rule the committed tiled pair already used", () => {
+    // The check that this is the rule actually in use, not one that merely fits.
+    const tiledDisplay = parseTransform(BRAND_GLYPH_TRANSFORM);
+    const tiledChrome = parseTransform(BRAND_GLYPH_TRANSFORM_SMALL);
+    expect(tiledDisplay.x - tiledChrome.x).toBeCloseTo(5 * tiledDisplay.scale, 2);
+  });
+});
+
+describe("the variants are selected as whole sets", () => {
+  // Mixing one variant's point with the other's placement puts the glyph
+  // off-centre; the doc calls that out by name. One selector makes it unreachable.
+  it("pairs each stroke with its own point and placement", () => {
+    expect(brandMarkOptics("display")).toEqual({
+      transform: BRAND_GLYPH_TRANSFORM_BARE,
+      stroke: BRAND_STROKE_PATH,
+      point: BRAND_POINT,
+    });
+    expect(brandMarkOptics("chrome")).toEqual({
+      transform: BRAND_GLYPH_TRANSFORM_BARE_SMALL,
+      stroke: BRAND_STROKE_PATH_SMALL,
+      point: BRAND_POINT_SMALL,
+    });
+  });
+
+  it("keeps the cuts genuinely different", () => {
+    expect(BRAND_STROKE_PATH_SMALL).not.toBe(BRAND_STROKE_PATH);
+    expect(BRAND_POINT_SMALL.cx).toBeGreaterThan(BRAND_POINT.cx);
+  });
+});
+
+/** The brand doc's threshold: "at 32 px and below two things close up". */
+const CHROME_CUT_MAX_PX = 32;
+const REM_PX = 16;
+
+/**
+ * Tailwind `h-N` is N/4 rem; a CSS-module class is resolved to its own rule.
+ *
+ * The module lookup must go through the *specific* import identifier, not every
+ * `.module.css` the file imports. `ward-management-navigation.tsx` imports two
+ * modules and BOTH define `.brandGlyph`, at 2.5rem and 2rem — an identifier-blind
+ * resolver merges them and reports every site there as spanning 32-40px, which
+ * is a defect in this helper that reads exactly like a defect in the source.
+ */
+function renderedHeightsPx(className: string, sourcePath: string): number[] {
+  const cssModule = /\{\s*(\w+)\.(\w+)\s*\}/.exec(className);
+  if (!cssModule) {
+    return [...className.matchAll(/(?:^|\s|:)h-(\d+)\b/g)].map(([, n]) => (Number(n) / 4) * REM_PX);
+  }
+  const [, identifier, cssClass] = cssModule;
+  const source = readFileSync(sourcePath, "utf8");
+  const importPath = new RegExp(String.raw`import\s+${identifier}\s+from\s+"([^"]*\.module\.css)"`).exec(source)?.[1];
+  if (!importPath) return [];
+  const css = readFileSync(path.resolve(path.dirname(sourcePath), importPath), "utf8");
+  const rule = new RegExp(String.raw`\.${cssClass}\s*\{[^}]*?height:\s*([\d.]+)rem`, "s").exec(css);
+  return rule ? [Number(rule[1]) * REM_PX] : [];
+}
+
+describe("every production call site draws the cut its size needs", () => {
+  const files = execFileSync("git", ["ls-files", "src"], { encoding: "utf8" })
+    .split("\n")
+    .filter((file) => file.endsWith(".tsx") && !/mockups?\b/.test(file));
+
+  const callSites = files.flatMap((file) => {
+    const source = readFileSync(file, "utf8");
+    return [...source.matchAll(/<BrandMark\b([^>]*?)\/>/gs)].map((match) => ({
+      file,
+      attributes: match[1],
+      optical: /optical="chrome"/.test(match[1]) ? "chrome" : "display",
+      heights: renderedHeightsPx(
+        /className=(?:"([^"]*)"|(\{[^}]*\}))/.exec(match[1])?.slice(1).find(Boolean) ?? "",
+        file,
+      ),
+    }));
+  });
+
+  it("finds the production call sites at all", () => {
+    // Guards the scan itself: a regex that silently matches nothing would make
+    // every assertion below pass vacuously.
+    expect(callSites.length).toBeGreaterThanOrEqual(10);
+    expect(callSites.every((site) => site.heights.length > 0)).toBe(true);
+  });
+
+  it.each([
+    ["never straddles the threshold, which would need a human decision", "straddle"],
+    ["draws the chrome cut at 32px and below", "chrome"],
+    ["draws the display cut above 32px", "display"],
+  ])("%s", (_name, mode) => {
+    for (const site of callSites) {
+      const smallest = Math.min(...site.heights);
+      const largest = Math.max(...site.heights);
+      if (mode === "straddle") {
+        expect(
+          smallest > CHROME_CUT_MAX_PX || largest <= CHROME_CUT_MAX_PX,
+          `${site.file} renders ${smallest}-${largest}px, spanning the ${CHROME_CUT_MAX_PX}px cut ` +
+            "threshold. One element draws one cut, so pick deliberately rather than by rounding.",
+        ).toBe(true);
+        continue;
+      }
+      if (mode === "chrome" && largest <= CHROME_CUT_MAX_PX) {
+        expect(site.optical, `${site.file} renders at ${largest}px and needs optical="chrome"`).toBe("chrome");
+      }
+      if (mode === "display" && smallest > CHROME_CUT_MAX_PX) {
+        expect(
+          site.optical,
+          `${site.file} renders at ${smallest}px, above the small-cut range; the widened gap is not for it`,
+        ).toBe("display");
+      }
+    }
+  });
+});