:::The last time I fooled around with links it didn't have an obvious effect right away, but I can't claim to have investigated it very well.  I am not an expert in Googleology (and I know there are many people out there who are) but my guess is that somebody in their company actually sees reports of what fraction of their search results lead to Wikipedia and would be in a position to compensate for changes that result from https, overlinking, etc.  I think it would be far more plausible for someone linked with a company to find a way to "SEO" that company's article in particular.