In an attempt to avoid submitting a ratings dispute to an American regulatory agency, the WBC has declined to participate in an arbitration before the Association of Boxing Commissioners (ABC). The arbitration was demanded by Main Events on behalf of Fernando Vargas, who was going to challenge Javier Castillejo for the WBC 154-pound championship.  In response to the arbitration demand, the WBC cited its rule 5.4 which requires the arbitration be conducted by the Court of Arbitration for Sports, which is located in Lausanne, Switzerland but maintains an office in New York.

As the bout between Vargas and Castillejo was being finalized, the WBC said Castillejo had to face Ricardo Mayorga next, and stripped Castillejo. Vargas and Castillejo will fight anyway on August 20, 2005, just one week after Mayorga and Michelle Piccirillo are tentatively scheduled to contest the vacant title.

In a June 9, 2005 letter to the ABC, the WBC defended its decision to make Mayorga the mandatory even though he was coming off a September loss to Felix Trinidad.  "There are countless examples demonstrating that top level fighters like Mayorga have been rated highly even after being defeated, when performing well in great fights against great opposition."

Main Events position is that, by ordering Castillejo to make a mandatory defense against Mayorga, who it currently rates in the #2 position, the WBC has violated its own rule, namely rule 1.26, which states, "The WBC shall order a final elimination bout to determine the mandatory challenger, except in situations where by vote of the majority of the WBC Board of Governors, it is determined that the number one rated challenger has the merits to be the mandatory challenger." According to the letter, Mayorga became the WBC's mandatory contender when, among other things, #1 rated Oscar De La Hoya moved up to middleweight and lost to Bernard Hopkins.

In a June 10, 2005 response to the WBC, Main Events attorney Patrick English wrote that the WBC is spreading a "big lie" because the WBC rated De La Hoya #1 at 154 pounds AFTER he lost to Hopkins and therefore, De La Hoya was not really unavailable.  English noted that the WBC never addressed why it ignored the elimination bout rule, and then submitted the dispute to the ABC. However, the ABC has not been totally clear about whether it intends to enforce any decision it might reach or merely issue an advisory opinion.