at the end of the day, it's a speculative market and most of the time a "rebrand" signals a new development for a project, in fact, when the news broke out on LSK, it rose to about 40-70%, However this movement in price have to be substantiated otherwise, a reverse effect will happen and you lose the investors' confidence on the project.
Interesting to note that while investors buy the coin for a long term investment, there are "traders" who just look out for this price movements oftentimes these are the "day-traders" who after a certain gain would take profit straight away regardless of what coin it is or whatever news they read. Eventually, a pull-back of the price may happen which is actually showing with LSK now sitting comfortably at around 0.002 but still at 40% increase from before the news broke out.