Anytime you have both vesting schedules and at-will employment, your employer can fire you at any time and you will not get any unvested stock. Startups need to do this all the time when employees are underperforming or a bad fit. Renegotiating so that you can get a portion of that stock and stay employed is perhaps, if this were an isolated incident, a much better deal for the employee than getting fired.
Where this becomes very distasteful is if these aren't isolated incidents of very underperforming employees but Zynga using its leverage to negotiate compensation down arbitrarily. Even if a developer is performing just as well as expected upon hiring, it is unlikely that they could get a guaranteed offer of $1M from another company, and so Zynga could easily force a renegotiation of an unvested grant worth $5M down to $1M. This would be reprehensible - even if that employee isn't really adding $5M worth of value, if they are performing up to the expectations that were set when they were hired then the agreement should be honored - getting a chance of a huge upside is one of the reasons employees take lower salaries and work longer hours at startups in the first place. A company that abused its bargaining position like this should not expect to be able to hire good employees in the future.
There isn't really enough information in the article to know that this latter case is what's happening. There are scenarios in which this behavior is very malicious, and scenarios in which it's relatively reasonable. It all hinges on how the employees in question were performing and how common this tactic is. I don't think anybody here knows those details, so we should really try and avoid the typical internet rush-to-judgement here. I don't know anything about the internals of Zynga, but I have seen HN get out the pitchforks for other companies when the real story turned out to be much more mundane.
Where this becomes very distasteful is if these aren't isolated incidents of very underperforming employees but Zynga using its leverage to negotiate compensation down arbitrarily. Even if a developer is performing just as well as expected upon hiring, it is unlikely that they could get a guaranteed offer of $1M from another company, and so Zynga could easily force a renegotiation of an unvested grant worth $5M down to $1M. This would be reprehensible - even if that employee isn't really adding $5M worth of value, if they are performing up to the expectations that were set when they were hired then the agreement should be honored - getting a chance of a huge upside is one of the reasons employees take lower salaries and work longer hours at startups in the first place. A company that abused its bargaining position like this should not expect to be able to hire good employees in the future.
There isn't really enough information in the article to know that this latter case is what's happening. There are scenarios in which this behavior is very malicious, and scenarios in which it's relatively reasonable. It all hinges on how the employees in question were performing and how common this tactic is. I don't think anybody here knows those details, so we should really try and avoid the typical internet rush-to-judgement here. I don't know anything about the internals of Zynga, but I have seen HN get out the pitchforks for other companies when the real story turned out to be much more mundane.