For one week, the NFL will relax its rules and allow players to share personal messages on their cleats.

The NFL is planning to relent on its notoriously strict uniform policy this season, but only for a week, SI.com has learned.

There are a few more catches, but according to a league source you’ll see more personal messages on players’ cleats in Week 13. The NFL is planning to allow players to promote a charitable cause of their choice during the Dec. 4 weekend, and a separate league source indicated that plan will go beyond cleats.

There are some regulations, though.

Players must have the charity or cause approved by the league prior to Week 13, as the league will still determine the legitimacy of the cause. The players must also auction off the cleats after use and donate 100 percent of the proceeds to that charity or cause.

A league spokesman declined to comment. The NFL could announce this plan as early as this week.

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The league’s uniform policy has this to say about personal messages: “[P]layers are prohibited from wearing, displaying, or otherwise conveying personal messages either in writing or illustration, unless such message has been approved in advance by the League office. Items to celebrate anniversaries or memorable events, or to honor or commemorate individuals, such as helmet decals, and arm bands and jersey patches on players’ uniforms, are prohibited unless approved in advance by the League office….

“The League will not grant permission for any club or player to wear, display, or otherwise convey messages, through helmet decals, arm bands, jersey patches, or other items affixed to game uniforms or equipment, which relate to political activities or causes, other non-football events, causes or campaigns, or charitable causes or campaigns.”

Some players wore 9/11-inspired cleats this past weekend that did not adhere to the policy despite the possibility of a fine. Fines from the Week 1 games won't be announced until later this week.

Fines for sending personal messages on NFL uniforms have been going on for more than a decade. One of the most prominent early examples was in 2004 when Jake Plummer wore a helmet decal of his former teammate, Pat Tillman, one extra week. The NFL eventually withdrew the fine after Plummer took the decal off the following week. Former Bears receiver Brandon Marshall wore green cleats in 2013 to promote mental health awareness. He was fined $10,500 by the league.

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But the biggest controversy came last season when Pittsburgh running back DeAngelo Williams, widely credited for starting the league’s pink initiative in October to promote breast cancer awareness, was fined $5,787 for writing “Find the Cure” on his eye black.

The fine came after the league said Williams couldn’t wear pink all year long. He then decided to keep the tips of his hair pink since the league could not fine him. Williams’s mother died from breast cancer in May 2014.

This new, one-week policy will still raise questions. How will the NFL set its threshold for approval? No reasonable person would be against raising money and awareness for, say, children with cancer. But what of support for the local police union or the Black Lives Matter movement? We will soon find out.