This offer was supposed to expire yesterday, but the page is still loading and a colleague linked her accounts this morning, with points already posting this afternoon. I’d take advantage of this ASAP if you haven’t yet.
Back in August, Marriott was offering 500 points for linking your Instagram profile to your Marriott Rewards account.
They brought back that offer along with 500 point offers for both Facebook and Twitter as part of their “30 Days of Members Get it”. In total, you can earn 1,500 Marriott Rewards points, the equivalent of 500 Starpoints when transferring points from Marriott to SPG. Check out the full detail page here which notes a 12/7/16 deadline.