Heading into the 2016 Olympic Games in Rio de Janeiro, new changes to guidelines made by the U.S. Olympics Committee (U.S.O.C.) are giving startups the opportunity to steal marketing dollars from corporate giants. 

For years, companies were banned from  advertising around the Olympics unless they were official sponsors. (Becoming a sponsor can cost upwards of $25 million, sources told Reuters.) Now, the so-called "Rule 40" revisions allow unofficial sponsors to endorse Olympic athletes, and run ad campaigns during the games. 

The caveat, however, is that such companies are not permitted to use the U.S.O.C.'s copyrighted language, including imagery of the rings, or even the word "Olympics." 

Under Armour, which is not an official sponsor of the Olympics, is one such company making an aggressive marketing push around the Games--set to take place August 5 - 21. The sportswear giant has endorsed about 250 athletes, and is planning number of campaigns to shore up sales, a spokesperson tells Inc.

"The Olympics provide a unique platform for our brand to engage a global audience, and the changes to Rule 40 allow us to fulfill our number one objective: to support the nearly 250 Olympic athletes and hopefuls tied to the brand during the Games," said Peter Murray, Under Armour's VP of Global Sports Marketing.

Under the restriction of not using Olympics-branded language, Under Armour has gotten creative. Its global campaign "Rule Yourself," for instance, features footballer Memphis Deepay, athletes from USA Gymnastics, and Michael Phelps. A phrase like "the world's biggest stage" talks about the Olympics without actually using the event's intellectual property. One ad depicts gymnasts practicing routines on the bars, beam, floor, and vault. In another, Phelps is shown darting gracefully through a dark pool. The accompanying tag line is vague: "It's what you do in the dark that puts you in the light."

Paul Swinand, an analyst with research firm Morningstar, says the Rule 40 changes will "democratize" access to Olympics dollars. This, however, "assumes a small business is getting a proper return on investment for sponsoring one affordable athlete," he said.

To his point, companies sponsoring athletes (or in some cases, teams) are required to submit their plans to the U.S.O.C., or another national committee, for approval as many as six months ahead of the Games. That's well before athletes even know if they've qualified to compete in the event. According to Reuters, hundreds of brands applied for marketing waivers this year.

Meanwhile, traditional giants and official Olympics sponsors, like Nike and Visa, now stand to win less from their multimillion-dollar ad campaigns because of increased competition. McDonald's, for one, says it plans to work with media monitoring agencies to flag unofficial sponsors violating the terms of the deal. 

"If we find Rule 40 impacts the value of our sponsorship, we could always go back and renegotiate for the future," a spokesman for McDonald's told Reuters. "I wouldn't necessarily say we're all happy about it."