Microsoft is urging a D.C. federal court to make sure that the limits imposed on Google in the U.S. Department of Justice's search monopolization case prevent the search giant from inking multiyear default agreements and that they reach new types of generative artificial intelligence products.

Microsoft Corp. filed a proposed amicus brief Tuesday in the DOJ's search monopolization case against Google LLC as U.S. District Judge Amit P. Mehta mulls how exactly to craft a package of remedies for the antitrust violations he found last year.

The case centers on distribution agreements Google has with Mozilla, Apple, Samsung and other companies that make its search engine the default on their browsers and devices in exchange for billions of dollars in shared annual ad revenue.

The judge has already declined to bar Google from inking default agreements, while also rejecting efforts to force a sale of the Chrome browser, but has said he will put some limits in place while also requiring Google to prop up rivals with data-sharing measures.

Microsoft's brief on Tuesday urges the court to reject Google's efforts to continue using multiyear default agreements, even if they have annual opt-out provisions, and to accept the government's proposal of a one-year term. It also urged the court to adopt a more expansive view of artificial intelligence products that the order would apply to.

"As one of Google's main competitors in general search, Microsoft has firsthand experience with the harmful effects of Google's exclusive and anticompetitive distribution agreements, as well as the broader challenges posed by data access barriers, restricted market opportunities, and Google's dominance," the brief says.

Microsoft's Bing search engine is a main rival to Google Search, and the company also competes with Google's generative artificial intelligence offerings through Copilot and new "AI Agents" that combine general search with chatbots.

Tuesday's brief says that Microsoft is seeing similar issues in the AI space that it witnessed in search and argues that the court has already made clear that Google shouldn't be able to use the "same anticompetitive playbook" in AI that it used in search.

To this end, the brief says the DOJ is asking that the limits on default agreements apply to current generative AI offerings, as well as emerging AI agents that frequently invoke web searches to "fulfill a broad array of information needs." Google, on the other hand, is trying to narrow the order's application to products whose principal function is "answering information-seeking prompts," the brief says.

Google's "principal function test is unworkable and inconsistent with the court's findings and the remedies phase record," Microsoft says in the brief. "Modern GenAI is multifunctional and increasingly embedded across different products … where it competes by fulfilling broad informational needs."

Google's proposal would exclude AI agents that perform functions such as drafting emails or booking travel, the brief said, even though they routinely invoke web searches to answer user queries.

The brief says Google is already constraining the distribution of some generative AI products though its contracts with manufacturers, noting instances where manufacturers have declined to preinstall Copilot based on concerns about breaching their agreements with Google.

Microsoft also is urging the court to adopt the government's proposed language allowing it to retain jurisdiction to enforce and modify the final judgment if needed and to allow a technical committee to resolve disputes over compliance.

The input comes after OpenAI lodged a proposed amicus brief last week urging the court to apply flexibility to mandates requiring Google to syndicate its search results to would-be rivals. OpenAI said Google's proposal on the syndication requirements "would effectively gut" those remedies by limiting competitors' to displaying a syndicated list of 10 blue links.

Google hit back, contending the brief was really a bid for the court to reconsider OpenAI's rejected request to use the data to "ground" its artificial intelligence model.

Privacy-focused search rival DuckDuckGo also submitted a proposed amicus brief dealing with the data-sharing measures before Judge Mehta held an early October hearing on the competing proposals.

A representative for Microsoft declined to comment beyond the brief Wednesday. Representatives for Google and the DOJ did not immediately respond to requests for comment.

Microsoft is represented by John (Jay) Jurata Jr., Julia Chapman and Russell P. Cohen of Dechert LLP.

The federal government is represented by David Dahlquist, Adam Severt, Veronica Onyema, Travis Chapman, Diana Aguilar, Sarah Bartels, Grant Fergusson, Kerrie Freeborn, Meagan Glynn, Richard Cameron Gower, Karl Herrmann, Ian Hoffman, John Hogan, Elizabeth Jensen, Ryan Karr, Claire Maddox, Michael McLellan, Keane Nowlan, Andrew Tisinger, Jennifer Wamsley and Catharine Wright of the U.S. Department of Justice's Antitrust Division.

The states are represented by their respective attorneys general and William F. Cavanaugh Jr. of Patterson Belknap Webb & Tyler LLP.

Google is represented by John E. Schmidtlein, Benjamin M. Greenblum, Colette T. Connor, Kenneth C. Smurzynski, Graham W. Safty, Christopher Yeager, Gloria K. Maier and Aaron P. Maurer of Williams & Connolly LLP, Michael S. Sommer and Franklin M. Rubinstein of Wilson Sonsini Goodrich & Rosati PC, and Mark S. Popofsky and Matthew L. McGinnis of Ropes & Gray LLP.

The cases are U.S. et al. v. Google LLC, case number 1:20-cv-03010, and Colorado et al. v. Google LLC, case number 1:20-cv-03715, in the U.S. District Court for the District of Columbia.