Barbour, a UK apparel company, sells shirts with a ‘flag’ on the breast pocket:
Levis sells apparel which has ‘tabs’ on the pockets. It owns various registrations for the tab.
Levis aggressively polices its tab trademarks. It sent a demand letter to Barbour, alleging infringement and dilution. Barbour brought a DJ action. Barbour notes third-party use of tabs.
Disclosure: I have a heavy cable-knit Barbour sweater which is over twenty years old, and a more recently-purchased Barbour wind-breaker.