Twitter reportedly made a $525m offer for Instagram before the photo-sharing service was acquired by Facebook.

The news, which was broken by the New York Times over the weekend, could spell trouble for Instagram if true, as the company’s CEO Kevin Systrom denied that Instagram had received any formal offers other than from Facebook at a California Corporations Department hearing in August.

The hearing was called by Facebook as a way of speeding up its acquisition of Instagram, first announced in April 2012, and was intended to determine if the Facebook deal offered the best return for investors.

The New York Times reports that Systrom and Mike Krieger, the other founder of Instagram, held meetings with Twitter in March and verbally agreed the $525m price. Whether this constitutes a formal offer is likely to be key to the matter.

Facebook, Twitter and Instagram have all declined to comment on the story so far.