Metaplanet, a Tokyo-listed hotel group that over the past year has recast itself as Asia's most active Bitcoin treasury firm, will be added to the FTSE Japan Index, further embedding the world’s largest digital asset into mainstream equity portfolios. The change was confirmed in an announcement from FTSE Russell's September 2025 semi-annual review on Friday, which upgraded Metaplanet from small-cap to mid-cap status, with the index inclusion taking effect after market close by September 19. Metaplanet's inclusion marks another "important milestone" as it attempts to stay "as Japan's leading Bitcoin treasury company, CEO Simon Gerovich wrote Sunday on X.  Shortly after Gerovich announced the inclusion, the company disclosed the purchase of an additional 103 BTC, bringing total holdings to 18,991 BTC. It also updated its capital structure, saying 49,000 stock acquisition rights were exercised in the week of August 18–22, adding 4.9 million shares and lifting the total to 722 million, a step that funds further Bitcoin purchases but leaves each existing investor with a smaller slice of the company. Eric Trump, appointed as a strategic adviser to Metaplanet in March, will reportedly attend Metaplanet's next shareholder meeting in Tokyo in September, according to a Friday report from Bloomberg. Part of the FTSE global equity index series, the FTSE Japan Index tracks mid and large-cap companies listed in Japan. Funds that track the index automatically buy the stocks it lists. Passive inflow effects Metaplanet's inclusion in the FTSE Japan and All-World indices creates a "regulated route for BTC exposures" and "paves the way for other crypto-forward companies to join major benchmarks," Vincent Liu, chief investment officer at Kronos Research, told Decrypt. In effect, "passive flows into the FTSE indices" could "channel institutional capital" into Metaplanet to offer indirect Bitcoin exposure, boosting "liquidity and long-term stability" despite risks where large movements "could still ripple through both equity and crypto markets," Liu said. At a structural level, the promotion "shows that Bitcoin treasury strategies don't create barriers to index inclusion," Ryan Yoon, senior analyst at Tiger Research, told Decrypt. Metaplanet was likely evaluated "using standard criteria like market cap and trading volume, without separately considering their Bitcoin holdings," he added. However, the inclusion appears to represent "the existing index framework's neutral approach rather than active crypto acceptance, "Yoon noted. "Passive inflow effects exist structurally, but practical impact remains limited," Yoon said, explaining that while pension funds and index funds automatically purchase Metaplanet shares when tracking FTSE Japan, it produces "small index weighting," which means "minimal direct Bitcoin demand." What's problematic, according to Yoon, is that investors might "think they're making 'diversified Japan equity investments' while actually being exposed to both Bitcoin price volatility and the company's execution capability in acquiring Bitcoin." Now at nearly 64% of its 2025 goal, once Metaplanet reaches its 210,000 BTC target, the dependency on Bitcoin could intensify and potentially create "unexpected volatility for passive investors who didn't anticipate such crypto exposure," Yoon said.