NEW YORK (TheStreet) -- When Apple decided to finance some of its rising capital returns to shareholders in 2013, it prompted the biggest debt offering in corporate history at the time. Now that the company is planning to tap debt markets once more to boost dividend and buyback activity, Wall Street underwriters may be readying for a fee bonanza. Goldman Sachs and Deutsche Bank , the lead underwriters of Apple's first debt offering, are the most likely to benefit from Apple's decision to return to credit markets. In fiscal second-quarter earnings, Apple said it would increase its capital return to shareholders to over $130 billion by the end of 2015, with repurchases rising by $30 billion to $90 million.