Jonathan Gold, a spokesman for Americans for Free Trade, which has lobbied against the tariffs, said it was not clear which factors the United States trade representative, which is granting the exclusions, is considering, or why one company would receive an exclusion when another does not. “Until there’s transparency with the U.S.T.R. exclusion process, people are going to think certain companies are getting preferential treatment,” he said.

The trade representative responded that each exclusion “is evaluated on a case-by-case basis, taking into account whether the exclusion would undermine the objective” of an investigation the president has opened into Chinese intellectual property theft.

Apple products, which are largely assembled in China, have evaded some, but not all, tariffs. The company stands to be hit much harder by the final tranche of tariffs Mr. Trump threatened against China, which includes more consumer electronics. Some of those tariffs went into effect in September, and some are planned for Dec. 15.

Mr. Trump has vacillated between threatening Apple and holding it up as an example of how his policies are fueling American investment. The president tweeted in July that his administration would deny the company’s request for exemptions from the tariffs, saying they should instead make their products in America.

“Apple will not be given Tariff waiver, or relief, for Mac Pro parts that are made in China,” he tweeted on July 26. “Make them in the USA, no Tariffs!”

Since then, the company’s relations with the administration appear to have warmed.

Mr. Cook has periodically lobbied the president and his advisers on the negative effects of the trade war and his company’s contributions to the American economy. Apple has argued that it has no easy way of substituting the proprietary components that it designs in house and manufactures in China.