I would hope the intention is to buy and cancel as many shares as possible, thereby permenantly increasing the value of the remaining shares by as much as possible. Driving the price up in the short term would undermine that intention, and be a disservice to long term shareholders.
That said, they do seem to be taking it awfully slow. If they end up trying to buy 80% of the shares in the last 20% of the time period, it's going to be difficult to buy low.
DGX Price at posting:
23.3¢ Sentiment: None Disclosure: Held