I don't think it's illegal though but then why not do the same setup in the US and basically copy Saylor's strategy. Reason being the SEC I guess. I think it's dishonest and immoral or in a grey zone at least. It's a perpetual money printer for them. Buy BTC > increased share price > borrow against the shares > buy more BTC > ∞ (inbetween sell shares with huge profit > buy BTC for themselves and also owning a company worth hundreds of millions)