entry-content --> Previous ArticleA Bubble in Private Internet Companies?Next ArticleRabbi Is Sentenced in Plot to Shake Down SAC Capital Previous ArticleA Bubble in Private Internet Companies?Next ArticleRabbi Is Sentenced in Plot to Shake Down SAC CapitalMinh Uong/The New York TimesNot a Bubble, a Pyramid Scheme Mark Cuban on the sky-high Internet valuations: Our clients tend to be more sophisticated in their analysis than to rely solely on ratings from a single agencyBut among the shareholders of the