Short answer — the brands most commonly mentioned in stories, social posts and red‑carpet coverage about celebrity couples are:

• Rolex — ubiquitous choice for both men and women; often seen as a status gift or matching his‑and‑hers sport and dress models (Submariner, Daytona, Datejust, Day‑Date).
• Patek Philippe — associated with heirloom gifts, milestone anniversaries and high‑end couples (Nautilus, Aquanaut, Calatrava).
• Audemars Piguet — especially the Royal Oak/Offshore lines; popular with athletes, musicians and fashion‑forward couples.
• Omega — common luxury but more accessible alternative to Rolex; often appears in lifestyle and travel shots (Seamaster, Speedmaster, Constellation).
• Cartier — favored for elegant his‑and‑hers pairing and jewelry‑watch looks (Tank, Santos, Ballon Bleu).
• Richard Mille — mentioned in celebrity/athlete coverage for ultra‑high‑end, sporty statement pieces.
• Hublot — shows up in red‑carpet and sports partnerships (Big Bang, Classic Fusion).
• TAG Heuer — often linked with sporty or retro couple looks and brand ambassador pairings (Carrera, Monaco).
• Breitling — seen with adventure/aviation themes and sporty couple photos (Navitimer, Superocean).
• Bulgari — luxury jewelry‑watch crossover popular with celebrities, especially for women (Serpenti, Octo).
• Jaeger‑LeCoultre — classic dress watches and gifts, often in coverage of refined couple styles (Reverso, Master Control).
• IWC & Panerai — both show up with actor/athlete couples who favor large, masculine sport watches.

Why these brands appear most often

• Visibility: celebrities are photographed a lot (events, travel, paparazzi) so recognizable watches get noticed.
• Gifting & milestones: high‑value brands are often gifted for engagements, anniversaries, births or career milestones and get publicized.
• Brand ambassadorships: many celebrities are paid partners or ambassadors, which drives mentions.
• Matching/complimentary pieces: media likes “his and hers” or “he gave her” angles, so brands with both sporty and dress offerings are commonly covered.

If you want, I can:

• Give specific celebrity‑couple examples for each brand (I can look up recent mentions if you want current/dated examples).