McKesson Cites Loper Bright in Fighting IRS Over Cost Sharing

McKesson Corp. is invoking a key Supreme Court ruling that weakened agencies’ rulemaking authority in arguing that the IRS’s basis for a $9.6 million tax bill against the company is invalid.

McKesson sued the IRS last year over the tax bill, challenging an IRS rule that requires inclusion of stock-based compensation in cost-sharing agreements among its subsidiaries. That rule violates transfer-pricing principles, the company said—and in the wake of the high court’s 2024 Loper Bright ruling, courts no longer have to defer to the agency’s support of the rule.

“It’s time to finally let the invalid rule go, for good. ...