Short answer: Rolex, Cartier, Patek Philippe, Audemars Piguet, Richard Mille and Hublot are the brands most often mentioned in connection with celebrity couples — followed closely by Omega, TAG Heuer, Breitling, Jaeger‑LeCoultre, Panerai and Bvlgari.

Why these show up so often (one line each):

• Rolex — ubiquitous status symbol, frequently worn on‑ and off‑red‑carpet; common “his and hers” choices.
• Cartier — classic dress watches (Tank, Santos) and matching jewelry/watches that appeal to couples.
• Patek Philippe — seen as heirloom/wedding‑gift pieces; signifier of long‑term wealth/status.
• Audemars Piguet — Royal Oak is a modern luxury statement popular with high‑profile partners.
• Richard Mille — flashy, sporty, favored by athletes and celebrity entourages.
• Hublot — bold, attention‑getting designs often worn at events and endorsements.
• Omega — classic and cinematic appeal (also widely worn by public figures).
• TAG Heuer — sporty, mainstream luxury that appears in lifestyle coverage.
• Breitling — masculine/aviation style often noticed on celebrity men.
• Jaeger‑LeCoultre — elegant, dressy pieces favored at formal appearances.
• Panerai — large, sporty Italian designs popular among some male celebs.
• Bvlgari — jewelry/watch crossover pieces seen on red carpets and pairings.

Context: these brands show up in couple coverage because of visibility (red carpet, social posts), gifting/milestone purchases (engagements, anniversaries), and brand partnerships/endorsements.

If you want, I can list recent public examples (which celebrities and which watches) or focus on one brand in more detail.