Here’s a link to Google’s SEC form 8-K filing, laying out Page and Brin’s joint stock sale plan, filed Friday.

To give a sense of perspective, before the filing, Page and Brin together held approximately 54.6% of the voting shares of Google stock according to stats on all stock trading apps. If they follow the plan and sell all eligible shares, they will still, collectively, own approximately 52% of the voting shares.

That might seem insignificant. But wait.

As I read it (and the wording is a bit cryptic, so I could be off here), the plan calls for Page and Brin to sell, jointly, four million shares of stock. Four million shares. At Friday’s close of $549.01, that’s $2.2 billion. That is a huge amount of money.

One takeaway from all this is the massive amount of money a company like Google represents. Page and Brin are not ceding control of Google (they will still, together, own more than 50% of the voting shares). This is about diversifying their holdings:

These pre-arranged stock trading plans were adopted in order to allow Larry and Sergey to sell a portion of their Google stock over time as part of their long-term strategies for individual asset diversification and liquidity. The stock transactions pursuant to these plans will be disclosed publicly through Form 4 and Form 144 filings with the U.S. Securities and Exchange Commission. Using these plans, they will diversify their investment portfolios and spread stock trades out over an extended period of time to reduce market impact. Because these plans were established well in advance of any trade being made pursuant to them, they also help avoid concerns about whether these officers had material, non-public information when they made a decision to sell their stock.

Interesting.