After last month’s Facebook boycott, companies are demanding more control over how their ads appear online. And the tech companies seem to be listening.

For years, companies have complained that they pay good money for online ads, only to see them end up near a racist post or an article promoting a conspiracy theory.

Now major advertisers like Clorox and Coca-Cola, along with a number of large advertising agencies, are pushing the big tech companies to give them more control over where and how their ads show up.

The effort follows the advertiser boycott of Facebook last month, when more than 1,000 companies stopped buying ads on the platform to protest its handling of hate speech and misinformation.

Ben Hovaness, an executive at Omnicom Media Group, a company that manages $38 billion in global marketing spending, said it was time for the tech giants to go by the rules that applied before digital platforms were dominant.

“Advertisers buying TV ads, print ads, radio ads have for many decades had control over which programs or which pieces their ads appear next to or within,” Mr. Hovaness said. “Now that social advertising is a major portion of a lot of our clients’ budgets, having control over adjacency is just something that we see as essential as the ecosystem matures.”

Omnicom Media Group, known as OMG, has demanded that Facebook, Twitter and other tech companies do more than make promises that ads will be kept away from inappropriate content. It wants the big digital platforms to put systems in place to make sure that online ads will appear where companies are comfortable, and it wants proof that the systems work.

Mr. Hovaness also said that the reports on ad placement and ad performance provided by the tech companies were insufficient and should be supplemented by independent quarterly audits.

Greater control of ad placement and the independent measurement of ad performance were included in a list of proposals submitted recently to tech companies by the Council on Accountable Social Advertising, a lobbying group formed by OMG, along with dozens of clients, including Clorox.

Facebook, Reddit, Snap, TikTok, Twitter and YouTube have agreed to most of the proposals in principle, and OMG is monitoring the platforms to see if they update their practices.

The OMG campaign comes during a summer when tech companies have fallen under new scrutiny. In a congressional hearing last month, lawmakers interrogated the leaders of Amazon, Apple, Google and Facebook. Criticism has mounted over the proliferation of misinformation related to the coronavirus pandemic and the coming election on various digital platforms.

The ad industry is adding its grievances to the mix. In addition to the OMG-led effort, a newly formed coalition of trade groups, ad firms and companies, the Partnership for Responsible Addressable Media, is pushing back against planned changes from Apple and Google that are expected to disrupt how companies reach potential customers. IPG Mediabrands, an ad group, released an audit of nine tech companies last week.

But some industry watchdogs are skeptical of the efforts, especially at a time when companies spend more than half of their marketing budgets on digital platforms.

“It’s for optics, so they can appear to be doing something,” Augustine Fou, an independent ad fraud researcher, said. “The only thing that’s really going to have a long-term effect is when consumers or marketers revolt and actively stop using the platforms.”

Tech executives have defended their dealings with advertisers and pledged to do better.

“We fundamentally believe that our advertisers should have control over what content a user sees before and after their ad,” said Andrew Abbott, who is Reddit’s liaison to OMG.

Facebook cited its work with the Global Alliance for Responsible Media, an advertising trade group created last year to address toxic online content, and said that it had spent billions of dollars to keep hatred off its platform.

Tara Walpert Levy, the vice president of agency and brand solutions for Google and YouTube, said: “It is terrific to see Omnicom and others leaning in even further.”

Does that mean there will be peace between the advertisers and the tech companies? Mr. Hovaness, the OMG executive, sounded optimistic. Sort of.

“Now the really fun part starts,” he said. “The platforms are saying, philosophically, we agree with your construct of advertiser rights and remedies, and we think your clients are entitled to these features.”

He added, “We see this as a monthslong effort. Getting these partners to agree in principle is a key but early step. The odds of these platforms’ first pass at solutions being perfect is pretty low. And that’s fine.”