These are the biggest stock movers from Friday’s US session (May 22, 2026) — one up and one down for each market-cap tier. RGTI +19.87% led overall in the small-cap bucket. Each ticker block has the catalyst (or an honest “no clear catalyst” if there isn’t one) plus what a pattern-recognition algorithm would actually flag in the move — base breakout, momentum continuation, failed breakdown, sympathy selloff, or noise.

Mega-cap movers (Companies above $200B)

↑ MRK +5.64%

$122.41 · Mega-cap · $1.5B traded

Why: Merck rallied on fresh oncology data that analysts framed as opening ‘a new chapter’ in cancer treatment, easing fears the company is overly dependent on Keytruda.

Pattern: Clean breakout attempt from a multi-month base on heavy volume — the kind of news-driven gap-and-go a momentum filter would flag, though follow-through still needs confirmation.

↓ COST -2.11%

$1,028.24 · Mega-cap · $2.1B traded

Why: Costco drifted lower into next week’s PCE inflation print and retail earnings, with reports of a quiet credit-card change costing members money adding a small sentiment drag.

Pattern: Looks like normal mean-reversion from an extended uptrend on average volume — no base break, more profit-taking ahead of macro data than a real distribution signal.

Large-cap movers ($10B to $200B)

↑ QCOM +11.60%

$238.16 · Large-cap · $7.1B traded

Why: Qualcomm surged alongside a broader mobile-chip rally, with Skyworks and Qorvo also jumping as money rotated into non-Nvidia semiconductor names hitting fresh records.

Pattern: Textbook breakout on more than 3x typical dollar volume — clears a multi-quarter base with sector confirmation, exactly the setup a relative-strength scanner would surface.

↓ COIN -4.43%

$184.99 · Large-cap · $1.4B traded

Why: Coinbase fell alongside the broader crypto-stock complex, with no single clean catalyst — coverage pointed to several possible drags rather than one specific event.

Pattern: Looks more like noise than signal — a one-day pullback inside a wider range on unremarkable volume, no base break or failed-breakout structure to lean on.

Mid-cap movers ($2B to $10B)

↑ FUBO +6.67%

$9.75 · Mid-cap · $11M traded

Why: No clear catalyst in the last 36 hours — move appears tied to broader streaming-and-small-cap risk-on tape rather than company-specific news.

Pattern: Low dollar volume at $10M makes this look like a thin-tape bounce off a beaten-down base rather than a real momentum signal — easy to fade on most filters.

↓ FCEL -5.19%

$25.01 · Mid-cap · $297M traded

Why: FuelCell pulled back after a six-week green run that included a board upgrade — looks like profit-taking on a name that had stretched well above its base.

Pattern: Classic mean-reversion after a parabolic move on still-elevated volume — a momentum-exhaustion filter would flag the prior run as overextended and this dip as healthy.

Small-cap movers ($300M to $2B)

↑ RGTI +19.87%

$26.42 · Small-cap · $5.2B traded

Why: Rigetti jumped as quantum-computing names caught a bid on news of a $2 billion sector boost and renewed cyber-threat coverage, with IBM’s own quantum-driven rally lifting the cohort.

Pattern: Group-driven breakout on enormous dollar volume — relative to its $26 share price, $5.2B traded is a clear thematic-rotation signal, not a single-name idiosyncratic pop.

↓ GME -2.36%

$21.96 · Small-cap · $98M traded

Why: GameStop slipped after seeking shareholder approval to more than double its authorized share count, a move investors typically read as paving the way for dilution.

Pattern: Dilution-headline drift on modest volume inside an existing range — no clean base break either way, the kind of news-driven chop most pattern filters would skip.

Today’s biggest stock movers — bottom line

Friday’s tape was mixed — even split between up- and down-movers across the cap tiers. The Movers recap drops daily Tue-Sat morning Melbourne time, covering the prior US session’s biggest stock movers in every cap tier — mega, large, mid, and small.