Why tech companies hold so much cash and why it's naive to use EV = MC - cash for valuation

Source:

http://seekingalpha.com/article/224772-why-are-technology-ceos-so-reluctant-to-pay-dividends
http://seekingalpha.com/article/224992-microsoft-s-debt-sale-plans

Reason-1: Incentive. When managements hold large amount of options, they are inclined to not paying dividend but reserving cash to do buyback to hold stock price.
Reason-2: Wanting to do foolish acquisition.
Reason-3: Many US companies' cash are held oversea, so bringing them back involves transfer tax (hence MSFT's debt issuing plan, and you an really not do IV = MC - cash)

So you as a minority shareholders don't really 'own' those cashes on balance sheet! They are likely to be used for:

a) foolish acquisition (e.g. HP's recent acquisition);
b) stock buyback to offset option dilution (wealth transfer to management)