Korean retail investors who invest in U.S. stocks turned net buyers after 3 months. Selling of overseas stocks, driven by a strong domestic market and the influence of returning-to-domestic-market accounts (RIA), appears to have shifted back to net buying on the back of SpaceX listing.

According to the Korea Securities Depository's securities information portal, Seibro, on Tuesday, these investors net bought $233.66 million of U.S. stocks in June. Total purchases came to $1.10468 billion and total sales to $871.01 million.

It marked the first time since March that they posted net monthly purchases of U.S. stocks. They net sold $469.00 million in April and $939.77 million in May.

In April and May, selling pressure emerged as a sharp rise in the KOSPI combined with factors including returning-to-domestic-market accounts that offer tax exemptions when investors sell overseas stocks and return to the domestic market.

SpaceX listing was a major factor behind the switch to net buying in June. These investors bought $1.89307 billion worth of SpaceX shares last month.

As of June 29, their custody holdings of SpaceX were tallied at $1.74486 billion. That ranked 23rd among U.S. stocks widely held by these investors.

Excluding SpaceX, buying focused on semiconductors. The second-largest net purchase was memory chipmaker Micron at $640.51 million.

Roundhill Memory ETF posted net buying of $370.12 million, followed by Marvell Technology at $325.29 million. Roundhill Memory ETF holds global memory chipmakers including Samsung Electronics, SK Hynix and Micron.

On June 30 alone, they net bought $239.01 million of the Direxion Daily Semiconductor Bull 3X ETF, which tracks the Philadelphia Semiconductor Index three times on a long basis.

Their total custody holdings of U.S. stocks, however, fell. As of June 29, the total came to $189.92911 billion, down from $204.16072 billion at the end of May. A decline in share prices of some holdings appears to have had an impact despite the shift to net buying.