Shire is a Lexington company that got permission earlier this year to sell a drug that allegedly helps people with chronic dry eye disease. You know, like Restasis. But unlike the company that makes that, Shire's decided a good way to advertise their product is to fill the sidewalks of Boston with chalk ads overnight. The city reports it's sending out parks-department crews to deal with the dry chalk issue - by washing the crap off.
Shire's headquarters is conveniently located off the intersections of 128 and 2, should anybody wish to do a little impromptu chalking. We're sure they'd love it.