I'm talking about MagSafe, the connector used on some Apple power adapters that pops out of the socket easily, and snaps into place using a magnet, so that both the cable and the socket are unlikely to be damaged in the event of an unexpected disconnection.

MagSafe generation 1

Is this patented in such a way that only Apple can legally make a similar connector? I don't mean off-brand clones of MagSafe itself, but rather another style of connector which uses the same principle.

If so, when does the patent expire?


3 Answers 3


The connector is patented, as you see here. It contains 57 claims which define what is protected, and 35 USC 116 spells out the logic of claims (which, in a nutshell, says "this can get really complicated"). The set of claims defines what it patented, and infringement is defined in 35 USC 271 as

whoever without authority makes, uses, offers to sell, or sells any patented invention, within the United States or imports into the United States any patented invention during the term of the patent therefor, infringes the patent

that is, there isn't anything statutorily more specific about how similar similar is. Since the claims define what is protected, this generally is taken to refer to things that are the same w.r.t. to all of the claims. "Generally" means that there is a doctrine of equivalents, exemplified by Warner-Jenkinson Co. v. Hilton Davis Chemical Co. 520 U.S. 17, whereby a court may find infringement when there is an insubstantial difference between the allegedly infringing thing and the protected invention.

The Apple patent does not specify a specific number of millimeters between the contacts, so making a connector that is exactly the same as the Apple device (as marketed) but with different spacing on the connectors would be an infringement, because that spacing is not specified in a claim. A similar device that uses chewing gum rather than magnets to keep it together would not likely be found to be infringing since that is a substantial divergence from what Apple claims it has invented.

  • There are certain magnetic connectors from before 2005 that would certainly not be infringing the '526 patent. For example, the embodiments described in US Patent No. 6,030,229, do not infringe.
    – user3851
    Commented Apr 7, 2016 at 23:24
  • 1
    "X would be an infringement because X is not specified in a claim." That doesn't sound quite right. Isn't the burden on the patent-holder to show that its claims apply to alleged infringement? My understanding is that claims are specifically structured from general to specific because it is common for claims to be rejected (and, if granted a patent, attacked) as being overly broad or obvious, so an inventor starts with the most general claims possible, but backs them up with more specific ones should those be stricken.
    – feetwet
    Commented Apr 8, 2016 at 0:52
  • My point is that infringement is based in the claims, not a specific instantiation, so if a device differs from the instantiation, the claims, and not the instantiation, are what identifies an infringement. When a property is specified in a claim, then either having or lacking the property is irrelevant: the patent covers both possibilities. B.O.P. of course falls on the person asserting the claim to protection.
    – user6726
    Commented Apr 8, 2016 at 4:55

US Patent No. 7,311,526. Patent expiration depends in part on the payment of fees, so there's no officially announced expiration; however, the standard term is 20 years from filing, so sometime in 2025.

  • Are the claims broad enough that no one else may make a magnetic connector without Apple's approval? You've answered expiration, but not my main question.
    – Marsh
    Commented Apr 7, 2016 at 22:14

There is prior art for simpler versions of the the connector, that are apparently still used today.


"The basic concept of MagSafe is copied from the magnetic power connectors that are part of many deep fryers and Japanese countertop cooking appliances since the early 2000s in order to avoid spilling their dangerously hot contents.[2][3][4] Apple was granted US Patent No. 7311526 on MagSafe ("Magnetic connector for electronic device", issued in 2007) as MagSafe was deemed to be a sufficient improvement due to the connector being symmetrical and reversible, and the fact that magnets within a connector are arranged in opposing polarities for improved coupling strength."

So you could examine creating a connector design that doesn't violate the key innovations of the patent, the symmetrical/reversible & opposite polarities arrangement.

  • "key innovation" is not a concept in patent law. To infringe a claim in a patent, your device must meet all of the requirements of that claim. Commented Aug 20, 2018 at 6:29

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