Three companies. Nearly three-quarters of a fund’s entire portfolio. The Roundhill Memory ETF, trading under the ticker DRAM, has placed roughly 74.8% of its assets in Micron Technology, Samsung Electronics, and SK Hynix.
But investors don’t seem to mind. The fund hit $1 billion in assets under management within about 10 days of its April 2, 2026, launch. That kind of inflow velocity has drawn direct comparisons to the spot Bitcoin ETFs that reshaped crypto markets when they debuted.
Inside the concentration play
As of July 5, 2026, Micron Technology leads the portfolio at 25.96%, followed closely by Samsung Electronics at 25.40% and SK Hynix at 23.46%. Together, these three memory chip giants account for the vast majority of the fund’s exposure.
The remaining quarter or so is spread across other memory semiconductor names and related companies, with the ETF using a mix of equities and derivatives to build its positions. It carries an expense ratio of 0.65%, which sits in the mid-range for thematic ETFs but is notably higher than broad market index funds.
