Microsoft launched a seven-part $19.75 billion deal, the third biggest corporate bond offering of 2016, according to IFR data. Analysts said the deal’s $4.5 billion in 30-year bonds and $2.25 billion in 40-year bonds put particular pressure on 30-year Treasuries prices.

U.S. 30-year Treasuries prices fell more than a full point in price, with yields hitting a session high of 2.25%. Yields had hit a more than two-week low of 2.18% on Friday. The view that yields were likely headed higher after having fallen sharply on Friday also reduced demand for U.S. Treasuries.

“The Microsoft deal is a large enough supply/demand event in the market that it is uniquely driving yields a little higher,” said Justin Hoogendoorn, head of fixed income strategy at Piper Jaffray in Chicago.

Investors also took profits after the gain in Treasuries prices and drop in yields on Friday, which analysts said was magnified by institutional month-end buying.

“This is a little bit of a follow-through from late on Friday, when the prices got kind of silly because of month-end,” said Charles Comiskey, head of Treasuries trading at Bank of Nova Scotia in New York.

Comiskey also said Friday’s weaker-than-expected U.S. second-quarter gross domestic product growth data had reduced the likelihood of Federal Reserve interest rate increases any time soon, rendering Treasuries prices more vulnerable to daily flows and the pricing of corporate bond deals.

U.S. 30-year Treasuries prices were last down 1-15/32 to yield 2.25%, from a yield of 2.18% late Friday.

Benchmark U.S. 10-year Treasuries prices were last down 14/32 to yield 1.51%, after touching a more than two-week low in yield of 1.45% Friday.

Short-dated yields rose slightly. U.S. three-year Treasuries prices were last down 3/32 to yield 0.78%, from a nearly three-week low in yield of 0.75% touched Friday.