Schlage (pronounced // SHLAYG) is a lock manufacturer founded in 1920 by Walter Schlage in San Francisco. Schlage is one of the most popular brands of consumer and commercial locks in the United States. The company was acquired by Ingersoll Rand in 1974, and remained an Ingersoll Rand subsidiary for nearly 30 years. Schlage is currently a subsidiary of Allegion, an Ingersoll Rand spin-off formed in December of 2013. Schlage also produces high-security key and cylinder lines, Primus, Everest and Everest Primus XP. In May 2009, demolition began on the San Francisco headquarters of Schlage; though the original 1926 Spanish Colonial, designed by local architect William Peyton Day will remain, the rest of the Schlage headquarters is planned to become affordable, green housing.
There is no law against duplicating the reverse, numbered or quad-key blanks. They are not patented and are not protected against third-party manufacturing.
As of 2008, Primus keys are no longer protected by patents, therefore anyone is free to duplicate them. The Everest's patents will expire in 2014.
In addition to six cuts for standard locking mechanism, there are five side finger pins to operate the secondary sidebar lock. Primus keys will operate non-Primus locks within the same system. Primus blanks and keyways are slightly thinner to prevent the entry of non-Primus keys, however even if a standard key is altered to allow entry, it will not operate Primus locks. This design was protected until 2007 under U.S. Patent #4,756,177. The current generation Primus, called the Primus XP is a slight modification to the original design and is protected until 2024 under U.S. Patent #7,159,424. Schlage did not invent, nor do they hold the patents on Primus or Primus XP. The design is licensed to Schlage by Mr. Bo Widen of Torshälla, Sweden, the inventor and patent holder.
Features a patented under groove in the keyway design protected against cloning by utility patents until 2014. Relevant patents are: U.S. Patent #5,715,717 (December 2, 2016) and U.S. Patent #5,809,816. Just like the classic series, Everest Primus keys can operate Everest non-Primus locks, but not the other way around. Everest Primus XP is an extension to Primus Everest and the XP design is protected until 2024 under U.S. Patent #7,159,424. Schlage did not invent, nor do they hold the patents on the Everest keys. It was designed and patented by Bo Widen and licensed to Schlage.
Nexia Home Intelligence
Nexia Home Intelligence is a Home Automation System that allows users to remotely control and monitor home automation devices. A wireless network is created within the home and connects the wireless door lock to the internet. Using a smart-phone or a web-enabled computer, users can monitor and send commands to the Schlage Bridge, which communicates with Z-Wave enabled wireless locks, thermostats, lights, cameras, and other components within the home.
There is a monthly fee associated with the Nexia Home Intelligence service.
There are seven different keyways: C, CE, E, EF, F, FG, and G. There is also a special "P" keyway designed to accept any of the seven sectional keys and a special L key blank (35-101 L) designed to be accepted into all seven keyways. OEM L section blanks are made of stainless steel.
The older type. The common residential keyway is known as 35-100C, which is a five-pin, C section.
Horizontal mirror image of obverse keyways, no longer offered in new key systems and it is not available with Primus option.
Numbered or Paracentric (restricted)
A large family of keyways expressed as four numbers. Except for zeros, digits in the keyway designation cannot repeat; i.e. 3578, 1358 and 1200 are valid, but 1244 and 3300 are not. Primus cannot be implemented on this series. The digit 9 is not used. Each digit represents the presence of a notch in the keyway and a corresponding protrusion along the blade of the key. The odd digits 1, 3, 5, and 7 extend along the left side of the keyway as observed from the lock face from bottom to top. The even digits likewise, on the right side. Generally, keyways are identified by four non-zero digits in ascending order. In a large masterkey system, keys with fewer than four protrusions can be used to enter more than one keyway. For example, key blank 1460 will fit lock cylinder 1246, 1346,1467, etc.
Expressed in four characters, such as WSTP, VTQP, etc. This is a very large family, available in Primus.
At the 2013 DEF CON conference, MIT students David Lawrence and Eric Van Albert released a piece of code that allows anyone to create a 3D-printable software model of any Primus key. With just a flatbed scanner and their software tool, they were able to produce precise models that they uploaded to the 3D-printing services Shapeways and i.Materialise, who mailed them working copies of the keys in materials ranging from nylon to titanium. 
- "Schlage LiNK allows you to remotely manage access to your home video 2 of 4", Commercial by the Schlage company, uploaded by the YouTube user "SecureLocks"in 2009. Retrieved 2011-04-08.
- Haeber, Jonathan. "Schlage Lock, SF". Bearings. Retrieved 2009-06-23.
- http://everestprimus.schlage.com/essentials/mk101/keyway.htm Master Keying 101 accessed Apr 18 2008, now defunct.
- Everest FAQs - Everest Primus by Schlage