Key points
- Jane Street Group disclosed a 0.51% net short in Sivers Semiconductors (SIVEF), dated Aug 4.
- D.E. Shaw raised its short to 0.62% the same day, from 0.59%.
- No short seller was named in the register between July 23 and August 2. Total reported short interest is now 3%.
- Stockholm shares closed at SEK 33.96 Wednesday, down 8.36%.
Jane Street Group LLC now holds a publicly disclosed short position in Sivers Semiconductors. Sweden's Finansinspektionen put it at 0.51% of the issued share capital, dated August 4, in a register update posted Wednesday afternoon. The firm's previous position sat below the 0.5% level at which the regulator publishes a holder's name.
D.E. Shaw & Co LP appears on the same list at 0.62%, also dated August 4. That's up from 0.59% the day before, which was its first entry in the register.
Between July 23 and August 2 the list was empty. Voleon Capital Management dropped below the disclosure line on July 23. Two Sigma Investments had gone under it two days earlier, after running a position as large as 1.44% on July 8.
The register's Sivers entries, most recent first:
| Position holder | Position | Position date | Previous |
|---|---|---|---|
| D.E. Shaw & Co LP | 0.62% | Aug 4 | 0.59% |
| Jane Street Group LLC | 0.51% | Aug 4 | below 0.5% |
| D.E. Shaw & Co LP | 0.59% | Aug 3 | below 0.5% |
| Voleon Capital Management LP | below 0.5% | Jul 23 | 0.59% |
| Two Sigma Investments LP | below 0.5% | Jul 21 | 0.5% |
| Two Sigma Investments LP | 1.44% | Jul 8 | 1.15% |
Sivers reported 355,081,317 ordinary shares and votes in a July 31 release. Jane Street's 0.51% works out to about 1.81 million shares. D.E. Shaw's 0.62% comes to about 2.2 million. Together that's a little over 4 million shares, worth around SEK 136 million, or close to $14.3 million at Wednesday's close.
What the register says, and what it doesn't
Swedish rules require a fund to notify Finansinspektionen once its net short position passes 0.1% of a company's issued share capital. The name is published only above 0.5%. "Significant short net positions are positions that have passed 0.5 per cent of the issued share capital," the regulator says on the register page.
Total reported short interest in Sivers stands at 3% of the share capital. Jane Street and D.E. Shaw account for 1.13 percentage points of that. The rest belongs to holders sitting between 0.1% and 0.5%, and those names aren't published.
However, the register doesn't say why anyone is short, and it doesn't separate a directional bet from a hedge. Finansinspektionen doesn't check the filings before posting them either. "The data in this register is published automatically upon receipt of a notification to FI. The data is not reviewed prior to publication," the page says.
The stock gave back Tuesday's gain
Sivers closed at SEK 33.96 in Stockholm on Wednesday, down 8.36%. It opened at 37.58, a little above Tuesday's close of 37.06.
Tuesday was the up day. The stock rose 18.86% on a Reuters report that the FCC is drafting a ban on US imports of new Chinese optical transceiver models. Sivers supplies DFB lasers for a 1.6T transceiver module that Jabil said in April it plans to build.
The US line trades over the counter as SIVEF. It changed hands at $3.75 at 12:21 p.m. Eastern on Wednesday, against Tuesday's close of $3.88, on 430,139 shares.
Second quarter results are due August 27, before the open on Nasdaq Stockholm. A closed period under EU market abuse rules has run since July 28, so no insider transactions will be disclosed before the report lands.
Short seller Ningi Research published a report on June 1 arguing that about 31% of Sivers' 2025 revenue, some SEK 97 million, was dubious. Sivers hasn't published a rebuttal. Two US law firms opened investigations after that report. Bronstein, Gewirtz & Grossman still describes its Sivers matter as an investigation into potential claims, with no class period and no lead plaintiff deadline.
Finansinspektionen updates the register on weekday afternoons. Wednesday's list went up at 15:33 Stockholm time.
Sources
- Finansinspektionen, net short positions register, current and historic positions for Sivers Semiconductors AB (LEI 254900UBKNY2EJ588J53), list updated August 5, 2026 at 15:33 CEST
- Sivers Semiconductors, "Change in the Total Number of Shares and Votes in Sivers Semiconductors AB," July 31, 2026, source of the 355,081,317 share count
- Stockholm and US over-the-counter prices from Yahoo Finance, August 5, 2026, cross-checked against StockAnalysis for the Stockholm close. Dollar conversions use a USD/SEK rate of 9.4957
