Instagram appears to be cracking down on apps that use part of its name.

In new brand guidelines, the company ordered that “Insta” or “Gram” no longer can be used. It applies to new apps and apps now in use, which must be altered “within a reasonable period.” In the past, apps could not use the full Instagram name.

In its new policy, Instagram warns that its brand should not be used where there is an implication of an endorsement, partnership or sponsorship by the company. The Instagram brand can’t be combined with another company’s designs or marks. Also, domain names, logos, names, trademarks, or usernames can’t be used in a way that may be confused with Instagram.

“While we encourage developers to build great apps with Instagram, we cannot allow other applications to look like they might be official Instagram applications or endorsed or sponsored by us,” Instagram said in a recent letter to one company: Luxogram. “Protection of its well-known trademarks is very important to Instagram. … It has always been against our guidelines to use a name that sounds or looks like ‘Instagram’ or copies the look and feel of our application. … Use of ‘INSTA’ and ‘GRAM’ for an application that works with Instagram is harmful to the Instagram brand. … It is important that you develop your own distinctive branding for your applications.”

Some other companies that may need a name change under the new policy include: Gramfeed, Statigram, Luxogram, Webstagram, Instadrop and Instagallery.

Instagram, which launched on Oct. 6, 2010, now has 130 million monthly active users. It was acquired last year by Facebook (News - Alert) for $1 billion in cash and stock. It is best known as a photo-sharing service.

Image via news.com.au