The statute requires "efforts that are reasonable under the circumstances" — a standard calibrated to the business, not an absolute one. RCW 19.108.010(4)(b).
Machen, Inc. v. Aircraft Design, Inc., 65 Wn. App. 319, 327, 828 P.2d 73 (1992), overruled on other grounds by Waterjet Technology, Inc. v. Flow International Corp., 140 Wn.2d 313, 996 P.2d 598 (2000) identifies concrete measures that have been held sufficient: advising employees of the existence of a trade secret, limiting access on a need-to-know basis, and controlling plant access. Conversely, public disclosure through display, trade journal publication, advertising, or carelessness can defeat protection.
Woo v. Fireman's Fund Insurance Co., 137 Wn. App. 480, 490, 154 P.3d 236 (2007) holds that allowing information to become public — even through carelessness — precludes trade secret protection for want of adequate safeguarding.
Certain disclosures do not forfeit protection. Boeing holds that information does not lose trade secret status through submission for certification, confidential disclosure to employees or suppliers, or publication of exhibits at trial. 108 Wn.2d at 52.
The pattern instructions list five factors for the secrecy inquiry: the extent to which the information is known outside the business; the extent to which employees and others within the business know it; the nature and extent of the measures taken to guard secrecy; the existence or absence of an express agreement restricting disclosure; and the extent to which disclosures to others indicated that further disclosure was prohibited. WPI 351.08.