Apple Inc., International Business Machines Corp. and Texas Instruments Inc. led dollar-denominated bond sales of $43 billion in the busiest week this year for high-grade technology companies as relative yields narrowed.

Apple, the largest U.S. maker of smartphones, set a record for the biggest corporate bond sale ever with its $17 billion six-part offering on April 30, according to data compiled by Bloomberg. IBM raised $2.25 billion and Texas Instruments sold $1 billion, bringing the number of investment-grade technology issuers in the market to three, the highest this year.

Apple kicked off the rush of issuance when it announced on April 23 that it was planning to raise debt for the first time in almost two decades to help fund a $100 billion capital reward for shareholders. Microsoft Corp., the world's largest software maker, came to market later that week with a $2.67 billion offering in euros and dollars followed by Texas Instruments, in their first sales this year, and IBM, which obtained record-low coupons on its first sale in three months.