The Adidas three stripes, also referred to as the 'three parallel bars' or the 'three parallel lines', is the primary brand design of Adidas. Adidas was referred to as the "three stripes company" by it's founder Adolf Dassler, therefore, it's brand design is usually referred to as the three stripes, rather than the three lines or three bars. The three stripes are sometimes designed with a straight line, but also with a jagged edge.
Adidas did not invent the three stripes design: it was developed by a Finnish sports brand named Karhu. Karhu were founded in 1916 by Ab Sportartiklar Oy, and continue to trade to the present day (2015). Karhu developed running spikes like Adidas would do, and used the three stripes design on their running spikes. At the 1952 Helsinki Olympic Games, athletes at these games - including Emil Zatopek - won 15 gold medals using Karhu spikes.
Adolf Dassler was a keen supporter and sponsor of the Olympic Games and took notice of Karhu's spikes at these games. Dassler purchased the three stripes design from Karhu for a thousand pounds sterling and two bottles of Scotch Whiskey. Adolf Dassler would state that purchasing this iconic design for such a low price was a cornerstone for the success of his fledging company.
The cornerstone of promoting Adidas as a brand is sponsoring people competing at sports tournaments. Some of the sports associations who organise events have attempted to limit the three stripes being displayed - notable the Wimbledon tennis tournament. Adidas also ran into issues with 'copycat' products throughout the 1950's and 1960's - as the company expanded and sales increased - due to it's products only being identifiable by it's three stripes design. This became a problem because other manufacturers could create products that closely resembled Adidas'.
Adidas released the trademarked Trefoil logo in 1971, and by combining the Trefoil logo and three stripes design, Adidas were able to create products that could not be copied. The three stripes design and Trefoil logo have been incorporated into the majority of Adidas' apparel, footwear and branding. However, not all of Adidas' products feature the three stripes; new products, like the Adidas Neo fashion brand, do not exclusively use the three stripes design.
In 2016, Adidas won a legal 'battle' to protect the use of it's 'stripe' design in the European Union.