Facebook and Twitter are clamping down on political ads ahead of the 2018 midterm elections in an effort to close loopholes that were exploited during the 2016 presidential campaign.

As of Thursday, all election and issue-based ads on Facebook and Instagram must be labeled and have a “paid for by” disclaimer. Users can click through to an archive, which will show the campaign budget for that specific ad, how many people saw it, and more details about viewers including age, gender and location. The archive will store this information for seven years.

Political advertisers in the United States will have to affirm their identity and location, following an announcement in April that requires verification for people buying political ads.

And Facebook is now grouping both issue-based and electoral ads under the umbrella of political ads. This move was prompted by the Russia-based Internet Research Agency’s penchant for stirring up emotion, without necessarily mentioning a specific candidate or election. For now, Facebook has identified 20 topics, from abortion to poverty, which fall under the “issues” category.

“The aim is for this effort to reflect the latest public discourse,” Katie Harbath, Facebook’s global politics and government outreach director, said on a call with media.

Facebook will partner with such organizations as the Comparative Agendas Project and market research agency YouGov to create a “living, breathing document” of issues that will evolve over time.

Likewise, Twitter announced Thursday that it’s placing more regulations on election ads. All advertisers for federal elections will have to certify that they are living in the U.S., and candidates and committees will have to provide their Federal Election Campaign identification.

Both companies have faced criticism from investors, politicians and users in the aftermath of the 2016 election, for allowing groups to mask as political entities and flood their networks with targeted political propaganda. Facebook said late last year that 126 million Americans may have seen content or ads created by Russian-backed trolls ahead of the election.

In a blog post, Harbath and Facebook public policy director Steve Satterfield said the company didn’t ban political advertising altogether because that would benefit politicians with large budgets who can rely on more expensive television, radio and newspaper ads.

“Digital advertising is typically more affordable than TV or print ads, giving less well-funded candidates a relatively economical way to reach their future constituents,” they wrote. “Similarly, it would make it harder for people running for local office — who can’t afford larger media buys — to get their message out.”

Harbath emphasized that Facebook was investing so much into policing political advertising that it likely would not make much revenue from it.

CEO Mark “Zuckerberg has said ‘We won’t make money off of political ads.’ We are investing a lot into this and the cost is worth it,” Harbath said.

“At Facebook, our ultimate goal is to help ensure people know who is trying to share messages with them,” she added.

Much of that cost will come from the security staff Facebook pledged in October to double to 20,000. On the call, Facebook staff said about 3,000 to 4,000 of those staffers would be dedicated just to assisting with these new political ad efforts, but machine learning would also be applied.

Twitter said that accounts used for political campaigns must have a profile photo, header photo and website that matches the entity’s online presence, and the Twitter bio has to include a website with valid contact information. All these changes will take place in coming months.

Twitter said on Wednesday it’s adding U.S. election labels for candidates running in the November midtermelections. Users will begin seeing them on Wednesday.

In the future, the company will add a badge and disclaimer for promoted political content from certified accounts. It will also introduce an “Ad Transparency Center” that has information on all ads running on its platform, and political ads will have data on how much was spent on the ad and who was meant to see it.