Photo website Instagram plans to modify its terms of service in the wake of a huge backlash over apparent plans to claim the rights of people's pictures and sell them to advertisers.
Instagram, owned by Facebook, updated its terms and conditions on Monday, sparking concerns that it now claims ownership over users' photos and can sell them to advertisers whether they consent or not.
But yesterday the mobile photo-sharing company released a blog post insisting it is not claiming ownership rights, and has no plans to sell pictures to advertisers.
"I'm writing this today to let you know we're listening and to commit to you that we will be doing more to answer your questions, fix any mistakes, and eliminate the confusion," he said.
"As we review your feedback and stories in the press, we're going to modify specific parts of the terms to make it more clear what will happen with your photos.
"Legal documents are easy to misinterpret. So I'd like to address specific concerns we've heard from everyone".
Mr Systrom said changes to the terms were hoped to show that Instagram wanted to experiment with innovative advertising.
"Instead it was interpreted by many that we were going to sell your photos to others without any compensation.
"This is not true and it is our mistake that this language is confusing. To be clear: it is not our intention to sell your photos. We are working on updated language in the terms to make sure this is clear."
On the issue of ownership rights, he wrote: "Instagram users own their content and Instagram does not claim any ownership rights over your photos. Nothing about this has changed.
"We respect that there are creative artists and hobbyists alike that pour their heart into creating beautiful photos, and we respect that your photos are your photos. Period.
"I always want you to feel comfortable sharing your photos on Instagram and we will always work hard to foster and respect our community and go out of our way to support its rights."
Earlier this month, tensions between Instagram and Twitter increased after Instagram restricted the way its pictures, known as "cards", are displayed on the microblogging service.
The relationship between the two has soured since Facebook bought Instagram for one billion US dollars (£620 million).
Instagram, which has rocketed in popularity since Facebook bought it in April, altered the feature, meaning pictures appear on Twitter badly cropped or deleted.
The move appeared to be a tit-for-tat retaliation after Twitter disabled the "find my Twitter friends" feature on Instagram in the summer.
Instagram's decision to modify its terms of service came after a wave of celebrities took to Twitter to criticise the company and urge fans to boycott the app.
Prominent American actors and musicians were among those who declared they would be deleting their accounts.
The messages were sent to millions of Twitter users and retweeted thousands of times in what amounted to an international PR disaster for the online photo-sharing service.
Singer Pink told her 12 million followers yesterday: "I will be quitting Instagram today. What a bummer. You should all read their new rules."
Actress Mia Farrow wrote "Trust me, deleting your Instagram account is satisfying", while Kate Walsh, star of Grey's Anatomy, simply posted: "No more Instagram."
Austin Powers and Family Guy actor Seth Green said he might delete his account, later writing that the new policy was about "selling ads against your pix w/out telling or including you".
Before yesterday's fury over the new policy, Instagram enjoyed overwhelmingly positive press from celebrities, with people such as Rihanna and Paris Hilton regularly sharing photos through the service.
But yesterday the tables turned, with celebrity outcry adding to the pressure that was building in the media for a change to the new policy.
The anger stemmed from a clause in the terms of service which sparked fears that Instagram could claim ownership over users' photos and sell them to advertisers without consent.
DJ and music producer Deadmau5 posted a picture of a raised middle finger with the words: "Here you go Instagram, feel free to sell this posted photo for cash. Thanks for selling me out."
The message was shared by other users on the site more than 1,000 times.
Canadian model Coco Rocha wrote that she was "horrified" by the new policy and said the idea that Instagram could sell your photos for free made them the "worst modelling agency" in history.
CNN anchor Anderson Cooper expressed his amazement at Instagram's new rules and urged his 3.4 million followers to recommend other photo apps.
Last night Instagram posted a message online thanking users for their feedback and pledging to clarify parts of the terms, stating: "It is not our intention to sell your photos."