All switchblades and knives that look like them are illegal to own or possess as well as daggers.
A dagger is any knife with double edges.
A knife with clipped section sharpened and clipped point are considered daggers thus cannot be carried or owned.
The Pennsylvania are strict with local ordinances since preemption law lacks. For instance, in Brotherly Love City, owning or carrying any knife outside your house is prohibited unless it’s a work knife.

Legal
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• It’s legal to own Pocket knives
• It’s legal to own bowie knives
• It’s legal to own hunting knives
• It’s legal to own fishing knives
• It’s legal to own utility knives
• It’s legal to own balisong knives
• It’s legal to own disguised knives like belt-buckle blades or dipstick knives
These legal knives can only be carried for purposes allowed by the law. The person carrying the knife should be able to demonstrate a lawful purpose, and it should be convincing.
Illegal
• It’s illegal to own daggers
• It’s illegal to own machetes
• It’s illegal to own switchblades
• It’s illegal to own automatic knives
It’s illegal to carry these knives in your home and cannot be made, sold, bought or given to other people within Keystone state.
Length Limit
Pennsylvania knife laws don't limit the blade length and thus owning or carrying a knife in this state doesn’t depend on its length.
Conceal Carry
It’s illegal to conceal carry automatic knives such as gravity knives and switchblades, daggers, sword canes. A knife owner can carry conceal legal knives as long as he/she can demonstrate the lawful purpose.
Other Knife Laws in Pennsylvania
Some municipalities such as Philadelphia outdo state legislation in strictness. Philadelphia ordinance prohibits using, possessing, or carrying any knife even pocket knives. There is an exemption when a knife is used at a moment of active exercise of trade. When this blanket ban is violated, there is a sentence of 90 days jail term and a fine of $300.
Conclusion
Carrying and owning a sword cane, automatic knife and a dagger is illegal in Pennsylvania. It's legal to conceal and open carry legal knives.
Sources
- 18 P.S. § 4416 (2013)