What are barrier of entry?

Tel me also advantages and disadvantages of Oligopoly?.

saturation of the markets it is looking to enter in

Patents establish a temporary monopoly, preventing other entities from developing the same products without a license.

Some examples: legal barriers (e.g.) state-enforced monopolies); high fixed capital costs (e.g.) automanufacturing); price manipulation by leading firms in uncompetitive markets (e.g.) leading firms...

Yes