Competitor got caught faking their contractor's license. Do I tell their clients?

I run a small residential roofing company (just me + 4 guys, doing around $40k/month) and there's one competitor who's always been our biggest rival in the area. We're cordial at supply shops but definitely competing for the same jobs. Last week I found out (through our shared insurance broker, long story) that they've been straight up lying to clients about having a general contractor's license. Like they claim to be "fully licensed and insured" on their website, truck wraps, everywhere. But t...