
Takate Kobayakawa, recognized as one of Japan’s most prominent “bedroom traders,” amassed a vast fortune trading stocks on the Tokyo Stock Exchange in the early 2000s. Starting with just ¥1.36 million, he famously grew his capital to approximately ¥1.53 billion in just eight years, earning legendary status after making ¥800 million in a single day. With frequent trades generating profits of several million yen, he continues to strive for even greater heights as a billionaire investor.
Within Japan’s trading circles, Kobayakawa is also known by his chatroom alias “BNF” and the nickname “J-Com Man.” Born on March 5, 1978, in Ichikawa, Chiba Prefecture, he began trading stocks during the 2001 bear market. Despite his status as a top Japanese day trader with multimillion-dollar assets, he’s known for his humility and avoids lavish cars or extravagant meals. His only notable luxury purchase has been a high-rise apartment bought for ¥400 million.
The name “BNF” is a tribute to Victor Niederhoffer, the American hedge fund manager, adopted by Kobayakawa to honor his mentor.
Kobayakawa’s journey was anything but easy. As a university student, he faced significant financial challenges and worked hard to support himself. Yet, he held an unshakable resolve to outperform the financial system.
His interest in stocks began when he saw a news broadcast about the market. At 20, with no money to his name, Kobayakawa became fascinated by the stock market. Determined to secure a better life, he studied technical analysis and set out to master market dynamics.
For two years, he took on various jobs to build capital while immersing himself in the complexities of stock trading. His persistence paid off as he started investing in Japanese equities during a bear market, remaining calm and rational even amid widespread fear and uncertainty.
In 2005, Kobayakawa made millions of yen in a single trade immediately after J-com Holdings’ IPO. The opportunity arose when a Mizuho Securities trader mistakenly sold 610,000 shares at ¥1 each, instead of selling one share at ¥610,000. This massive sell order caused the price to plunge, which Kobayakawa swiftly capitalized on.
He bought 7,100 shares during the crash, then sold part of his position during the rebound and held the rest overnight, reportedly earning over $17 million by the close of the trade. This windfall marked a major turning point in his career and proved his ability to consistently succeed in the markets.
It’s natural to wonder what strategies Kobayakawa used to generate millions in trading profits, but detailed information remains scarce. He has never fully disclosed his trades or shared much about how he achieved such high returns.
Kobayakawa believes bear markets present more opportunities than bull markets and focuses on short-term rebounds in declining stocks. His approach is commonly described as “divergent intraday trading,” using tools like Bollinger Bands, the Relative Strength Index (RSI), volume ratios, and the 25-day moving average to inform decisions. He is known for buying stocks that have dropped at least 20% below the 25-day moving average and profiting from their rebounds.
With markets in constant flux, he adapts his target ratios based on overall market conditions and sector performance, gauging how individual sectors move and the speed of their recoveries to guide his trades. Like many day traders, he prefers to capitalize on momentum, especially during market downturns.
Through discipline, consistency, reason, determination, and focus, BNF achieved extraordinary success. Within two years, he transformed his initial ¥1.36 million investment into an impressive $1.5 million, the first step toward becoming known as the investor who made ¥800 million in a single day.
However, BNF once strayed from his trading principles by investing in U.S. stocks instead of Japanese equities. During the housing market collapse, he invested heavily in bank stocks based on a mistaken belief that U.S. banks were collapsing, resulting in losses of over $10 million. This painful lesson reinforced the importance of sticking to trading principles and led him to adopt a more cautious approach in subsequent strategies.
Kobayakawa’s story is about more than financial achievement. His journey underscores the value of unwavering resolve, continuous learning, and strict adherence to market principles. Growing his assets from ¥1.36 million to several billion yen was possible thanks to sound strategy, psychological discipline, and a deep understanding of market behavior. His reputation as the investor who made ¥800 million in a single day demonstrates that even setbacks contribute to growth and form the basis for long-term success. In the world of trading, Takate Kobayakawa’s legend endures as a brilliant example that with the right knowledge, skill, and patience, ordinary people can achieve financial freedom.











