There are many cases where companies grasp their competitors within the narrow range of the same industry and fail to clearly understand their true rivals.
Literal
Companies [topic-は], competing-other-companies [obj-を] industry-inside [gen-の] narrow range [in-で] grasp-[and-て], true rival [obj-を] clearly understand not-[attr-していない] case [subject-が] many exists.
Formal business-analysis prose. 競合他社 ('competing other companies') is a compound noun. ~を[range]で[verb] is a common pattern for 'treating X within the scope of Y.' 捉える ('to grasp, to perceive, to conceive of') is a common analytical verb. ~していない場合が数多くあります ('there are numerous cases where X is not being done') is a formal statistical framing. The whole sentence has the measured, general-truth tone of a business consulting report.