Abstract This study investigates the effects of legal regulation, rule changes, and regulated trading instruments on Bitcoin’s price dynamics and volatility over the period 2013–2022. Using daily time-series data from major cryptocurrency exchanges and financial databases, the study employs a Vector Error Correction Model (VECM) models to capture both short- and long-run relationships under different market regimes. Empirical results reveal that regulatory announcements in the United States and Japan significantly influence Bitcoin’s price and volatility, indicating that legal recognition and enforcement mechanisms enhance investor confidence. In contrast, rule-change events such as hard forks and halving demonstrate asymmetric effects, initially increasing volatility before stabilizing over time. The introduction of Bitcoin futures and options strengthens market maturity and institutional participation but also introduces speculative dynamics, especially during high-volatility periods. The findings underscore the dual nature of regulation: while it promotes market legitimacy and long-term stability, it can simultaneously induce short-term uncertainty and price corrections. Policy implications highlight the necessity of a coordinated global regulatory framework that balances innovation with investor protection, while future research should explore algorithmic trading behaviors, DeFi spillovers, and cross-asset contagion effects in cryptocurrency markets. Keywords: Bitcoin, Regulation, Market Volatility, Hard Fork, Futures Options, Cryptocurrency.