Stronghold Digital Mining (NASDAQ:SDIG) shares slip despite Northland analyst Mike Grondahl initiating coverage at Outperform, according to a note he wrote to clients. Shares of SDIG -2% initially gapped up about 9% in pre-market trading, but has since erased all of those gains, changing hands in net negative territory. The analyst highlights the company's environmentally beneficial energy production, low-cost power generation and coal reclamation, in addition to efficient mining operations. In addition, "acquisitions are a large part of Stronghold's expansion strategy and management has a strong track record of acquiring and operating power assets," Grondahl says. Applies a $35 price target, implying roughly 30% upside from Friday's close. DA Davidson analyst Christopher Brendler also sets a Buy rating on SDIG, saying it "has the potential to outperform as it executes on its unique strategy," CoinDesk reports. The Bullish ratings agree with the Bullish SA Author Rating at 4.00. See why SA contributor