Indeed, and it is a legal matter at that:
LEGO Group Profile 2009
Please help us to protect our brand name:
• The LEGO brand name should always be written in capital letters
• LEGO must never be used as a generic term or in the plural or as a
possessive pronoun, e.g. “LEGO’s”.
• When the LEGO brand name is used as part of a noun, it must never
appear on its own. It should always be accompanied by a noun. For ex
ample, LEGO set, LEGO products, LEGO Group, LEGO play materials,
LEGO bricks, LEGO universe, etc.
• The first time the LEGO brand name appears it must be accompanied
by the Registered symbol ®.
Thank you for helping us!