The Center for Medical Progress (CMP)—the nonprofit group responsible for the discredited attack videos on Planned Parenthood beginning in summer of 2015—raised nearly half a million dollars in funding that same year, according to tax filings the group recently released.

CMP received only modest amounts of financial support in its first two years of existence, the filings show: In 2013, the group received $36,000 in contributions, and less than $60,000 in 2014.

By the next year, that support had leapt to $454,046, the documents show. It is unclear whether that funding came before or after the videos were released.

Those videos were part of what CMP called its “Human Capital” project, which sought to demonize the provision of fetal tissue for medical and scientific research—and by extension, to demonize abortion providers—with the broader aim of ending safe and legal abortion in the United States.

While none of CMP founder David Daleiden’s allegations of unlawful conduct on the part of abortion providers have been proven, the videos led to multiple state and federal investigations; renewed pushes in state legislatures and congress to “defund” Planned Parenthood; and contributed to an uptick in threats and violence against abortion providers throughout the country. In November 2015, Robert Lewis Dear Jr. admitted to murdering three people during an assault on a Planned Parenthood clinic in Colorado, muttering “no more baby parts”—an apparent callback to the videos—after he did so.

Who funded the years-long CMP project is a matter of great controversy. Indeed, CMP fought all the way to the U.S. Supreme Court in late 2015 to try to avoid handing over information containing the identity of “supporters” to lawyers for the National Abortion Federation (NAF), one of the groups that sued CMP and its officials after the release of the attack videos.

Nonprofit groups generally are required to file statements with the IRS and state regulators, in which they disclose the amounts of money they have received, as well as information including how they spent it, the identities and remuneration of key personnel, and statements on their organization’s mission. They are not, however, always required to disclose the sources of their funding.

In filing the 2015 tax documents with the California Registry of Charitable Trusts, CMP’s attorney went so far as to include a letter stating that the “included schedule of donors is marked ‘Confidential’” pursuant to a state law, which in turn refers to a federal code that appears to allow nonprofits to refuse to publish copies of their filings if they are “the subject of a harassment campaign.”

In other words, Daleiden and his associates now appear to be claiming that they are victims of harassment as a result of the videos they recorded and then released, and that the identities of their funders should therefore be protected by the state.

Despite CMP’s best efforts to withhold that information, the identity of their financial donors could ultimately become public, depending on how various litigation unfolds.

Lawsuits between CMP and NAF, and separately, between the group and Planned Parenthood, are ongoing. CMP lost its Supreme Court bid to avoid having to hand over records relating to who funded its activities as part of the NAF litigation, but those records remain under seal.

Last month, California’s new attorney general, Xavier Becerra, indicted Daleiden and one of his co-conspirators, Sandra Merritt, on multiple felony charges in connection with their secret recordings, which are illegal in that state.

Certainly, we are learning more about who has worked for CMP. As Rewire recently reported, Kellyanne Conway, senior adviser to President Donald Trump, worked as a consultant to the group in the year before her appointment to the Trump administration.