Organizers said "March Against Monsanto" protests were held in 52 countries and 436 cities.
The Supreme Court said that an Indiana farmer violated Monsanto Co.'s patents on soybean seeds that are resistant to its weed-killer.
The Supreme Court appeared likely Tuesday to side with Monsanto Co. in its claim that an Indiana farmer violated the company's patents on soybean seeds.
The Obama administration backs Monsanto in a patent rights case.
