How might this look? The key is that the benefit that can accrue to the original investors is capped. Any profit in addition to this would be the companies (perhaps held in trust for the current and future employees of the company). As such, the original capitalist investors are rewarded adequately for the risk that they take, but eventually are able to divest, leaving the company of the employees owned by the employees for the employees (although not directly via share ownership).
Why would the original investor want to cap his/her potential earnings? Well, this could be forced by government regulation (at this point the right-of-spectrum reader has no doubt had a heart attack!), but it might be an effective way to recruit a motivated workforce. Also, the original founders might like the possibility of leaving a public legacy (surprisingly few people are purely motivated by profit).
Are there any other downsides to such an approach? The cap on the original investor's benefit results in less capital owned by that original investor allowing him/her to create new companies. However, the capital still exists and is within the hands of an established organisation to help launch new products. This could lead to an overall trend for more stable companies, but fewer innovative startups. But then again, many of the wealthy who made their money from founding new companies don't invest in innovation, so it would be very difficult to assess this either way.
Conclusion: this is worth trying out.