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Apple’s big quarterly results not only helped its market cap hit the $1 trillion milestone, but it has helped buoy the broader markets, lengthening the long-in-the-tooth bull run. The Nasdaq is still near an all-time high despite recent disappointments by other tech giants, and the S&P 500 and Dow Jones industrial average are heading in that direction again.

And short sellers may be keeping an eye on two of their favorite stocks in the days ahead. That’s because Sirius XM Holdings Inc. (NASDAQ: SIRI) has been pulling back from a multiyear high back in June and Advanced Micro Devices Inc. (NASDAQ: AMD) is retreating from an even more recent multiyear high. Note that both of these are among the most shorted stocks traded on the Nasdaq.

The more than 198.20 million Sirius XM Holdings Inc. (NASDAQ: SIRI) shares held short after the first two weeks of last month was about 8% less than on the previous settlement date, or 15.2% of the available float. It was also the first time in at least a year that the short interest was less than 200 million. The average daily volume dropped sharply from near a year-to-date high, lifting the days to cover from more than eight to over 17.

One analyst was particularly bullish on Sirius during the period. The stock ended the short interest period trading about 5% higher, though it has pulled since then. The Nasdaq also climbed about 5% between the settlement dates. Sirius stock closed at $6.96 on Thursday. The 52-week low of $5.17 was reached early this year, while the $7.70 multiyear high was seen last month.

By the middle of July, Advanced Micro Devices Inc. (NASDAQ: AMD) had around 161.54 million shares short. That was 2.7 million or so less than the total on the previous settlement date, and it was the lowest level of short interest since February. The latest reading still represented 17.8% of the company’s float. Here too the average daily volume decreased sharply, but the number of days it would take to cover all short positions ticked up to less than four.

AMD made some management changes during the short interest period. Its shares ended the latest short interest period more than 8% higher, though they were up about 12% at one point. The stock closed trading most recently at $18.79 a share, which is more than 26% higher since the end of May. Shares have changed hands at between $9.04 and $20.18 apiece in the past year.

New short interest data are due out next week. That will offer a look at how the short sellers moved in the latter half of July, depending on whether the expected Sirius and AMD to rebound or tumble further, and how the most shorted stocks on the New York Stock Exchange and on the Nasdaq have fared overall.