Instagram co-founder and CEO Kevin Systrom is contrite this week.

The popular photo-sharing app, which Facebook bought in April for $1 billion, angered an untold number of users this week when it unveiled a new terms of service that seemed to say Instagram could sell its users’ photos to advertisers.

After a social media beating on Wednesday, Systrom made clear in a blog post late Wednesday that it was a big misunderstanding: Instagram isn’t selling your photos.

On Thursday night, he posted a follow-up blog with his apologies as well as details on a revamped terms of service.

“We failed to fulfill what I consider one of our most important responsibilities—to communicate our intentions clearly,” Systrom wrote. “I am sorry for that, and I am focused on making it right.”

Later in the post, he stressed: “I want to be really clear: Instagram has no intention of selling your photos, and we never did. We don’t own your photos—you do.”

Systrom also said Instagram has reverted its advertising section to the original version, and explained:

“Going forward, rather than obtain permission from you to introduce possible advertising products we have not yet developed, we are going to take the time to complete our plans, and then come back to our users and explain how we would like for our advertising business to work.”

The mea culpa, Systrom’s second since Wednesday, aims to pacify many of the Instagram members who grew indignant over the possibility that the platform would sell their photos to advertisers. Many of those members even canceled their accounts this week.

Regaining the trust of Instagram users might be an uphill battle, though. The Huffington Post insisted on Friday that “the worst part [of the terms of service] is still there.” According to HuffPost:

“But what Instagram left unchanged in its updated terms is actually more troubling. As Gerry Shih and Alexei Oreskovic of Reuters described nicely, there's other irksome language in the new agreement. One section implies that when a minor signs up for Instagram, he automatically has permission to do so from his parents.

“But more disturbingly, another clause makes it near impossible to take Instagram to court in any meaningful way. Users now can only join a class-action lawsuit if they ‘mail a written “opt-out” statement to Facebook's headquarters in Menlo Park within 30 days of joining Instagram,’ Reuters writes—which is not the case with Google, Twitter or Facebook proper.”

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