Uncle Richard's Contract is the contract that Richard Short used to sign Tag to Conservative Motors. On top of using Tag as a sponsor for CM, it also allowed Richard to claim that CM won the Crazy Crater race because of the signing.
In Career Mode[]
Initially, Richard tries to pressure Tag into signing, but he refuses due to his loyalty to Chief. However, after Richard's bomb detonated on Tag's Kart one night while Chief was working on it, Chief was severely injured, thus not being able to be Tag's crew chief (as well as Tag's boom box being out of commission due to the explosion). Because of this, on top of the fact Tag's Mother had no money to buy him another boom box, caused Tag to (reluctantly) sign with Conservative Motors. While this keeps Tag in the MRC, he receives backlash from his fans, hinting towards the idea that CM is not a well-liked company.
At the last scene of the career mode, the ModNation Police Department eventually found out about who planted the bomb that destroyed Tag's Kart, and proceeded to arrest Uncle Richard. This by extension took down CM (or at least, put it in questionable hands). Judging the public's impression on CM, this doesn't seem to be the first situation the company's been in.
Gameplay[]
Due to Tag signing the contract, the player will now be forced into a racing outfit sponsoring CM. Because of this, most people refer to this outfit as CM Tag. Uncle Richard also substitutes as the crew chief for multiple future races, but in the PSP version instead has no crew chief.