as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
why don't share prices of a company rise every other friday when the company buys shares for its own employees?
user
let's take an example: ibm has about 430,000 employees worldwide.  assume the average yearly salary is $80k (it's probably less, since a lot of jobs are offshore).  if every employee took 10% of their pay as stock, that's $132 million every two weeks.  but ibm's market capitalization is about $153 billion, so stock purchases would be less than 0.1% of that.
assistant