Actually it is. That's how Harmonix was sold by MTV for $50, or the old Japanese developer Jaleco, sold for $2.

You are both kinda wrong, the value of a company is loosely its assets minus liabilities, however the price to actually buy it outright is its market value PLUS its liabilities, because as Turkish mentioned the liabilities don't just disappear when you buy a company, they just transfer. An example would be a house, if say my house is worth $350k but I owe $250k on it, you couldn't buy my house for $100k because the bank still expects to get its $250k back. If Sony is worth $6 billion on the share market, if you buy it you take on those liabilities, so the total price to you is still market value plus liabilities. 

MS currently could afford to buy Sony based on market value (ie its share price * number of shares Sony has on the market) but then the problem is if Sony doesn't consent to be taken over MS has to do so in a hostile manner, by buying Sony shares as others sell them, and by doing so slowly accrueing an increasing share in Sony. The problem with a hostile takeover is as MS buys Sony shares the increased demand in Sony shares boosts the share price, costing MS an increasing amount to get, as Sony only has a set amount of shares available. A good example is when Porsche tried to take control of VW, but as they continued to buy VW shares the price kept going up (because you can only buy what people are prepared to sell) and eventually they took on so much debt trying to buy VW that they needed to be rescued (ironically by VW, which is why VW now own Porsche). Thats why hostile takeovers are difficult to do, and require massive amounts of capital (far higher than non-hostile takeovers). MS could probably do it, but its shareholders would be pissed as it would be a massive waste of money and would weaken MS considerably. Much better to wait until Sony is bankrupt and then buy the assets when its liquidatedand its assets are sold to pay off its liabilities  (not saying that will happen) . 

Anyway on topic, I don't think MS can do anything to win Japan, they tried buying exclusives this gen and it helped a tiny amount but not enough. Really I don't think they should care though, Japan is not that a big a market as it used to be, and they've shown this gen that you can still be successful without doing well in Japan. 

You are both kinda wrong, the value of a company is loosely its assets minus liabilities, however the price to actually buy it outright is its market value PLUS its liabilities, because as Turkish mentioned the liabilities don't just disappear when you buy a company, they just transfer. An example would be a house, if say my house is worth $350k but I owe $250k on it, you couldn't buy my house for $100k because the bank still expects to get its $250k back. If Sony is worth $6 billion on the share market, if you buy it you take on those liabilities, so the total price to you is still market value plus liabilities. 

MS currently could afford to buy Sony based on market value (ie its share price * number of shares Sony has on the market) but then the problem is if Sony doesn't consent to be taken over MS has to do so in a hostile manner, by buying Sony shares as others sell them, and by doing so slowly accrueing an increasing share in Sony. The problem with a hostile takeover is as MS buys Sony shares the increased demand in Sony shares boosts the share price, costing MS an increasing amount to get, as Sony only has a set amount of shares available. A good example is when Porsche tried to take control of VW, but as they continued to buy VW shares the price kept going up (because you can only buy what people are prepared to sell) and eventually they took on so much debt trying to buy VW that they needed to be rescued (ironically by VW, which is why VW now own Porsche). Thats why hostile takeovers are difficult to do, and require massive amounts of capital (far higher than non-hostile takeovers). MS could probably do it, but its shareholders would be pissed as it would be a massive waste of money and would weaken MS considerably. Much better to wait until Sony is bankrupt and then buy the assets when its liquidatedand its assets are sold to pay off its liabilities  (not saying that will happen) . 

Anyway on topic, I don't think MS can do anything to win Japan, they tried buying exclusives this gen and it helped a tiny amount but not enough. Really I don't think they should care though, Japan is not that a big a market as it used to be, and they've shown this gen that you can still be successful without doing well in Japan.