Proper service is a prerequisite to a valid default judgment. The court reviewed the legal adequacy of service de novo, although the ultimate decision whether to enter a default judgment is ordinarily reviewed for abuse of discretion.

Petrucelli mailed process to the Oklahoma Secretary of State within 120 days of filing suit. But Jake Diel was no longer a foreign corporation authorized to transact business in Oklahoma, and the Secretary therefore was not authorized to accept service as Jake Diel's agent. Service on the Secretary was ineffective, and a default judgment entered without proper service would have been void.

The Supreme Court's order adopting the 1993 amendments directed that they govern pending civil proceedings insofar as just and practicable. Applying Rule 4(m) was just and practicable here, even though Petrucelli attempted service under former Rule 4(j).

Former Rule 4(j) required dismissal when service was not made within 120 days and the plaintiff lacked good cause. New Rule 4(m) instead states that the court shall dismiss without prejudice or direct service within a specified time, while separately requiring an extension if the plaintiff shows good cause. The text therefore makes an extension mandatory with good cause but discretionary without it.

The Advisory Committee Note confirms that a court may relieve a plaintiff from Rule 4(m)'s consequences even without good cause. After finding no good cause, a court may consider equitable factors, including whether the statute of limitations would bar refiling or whether a defendant evaded service or concealed a defect in attempted service.

The expiration of the statute of limitations is not itself good cause and does not compel an extension. It becomes relevant only after the court finds no good cause, at which point the court retains discretion to dismiss even if dismissal effectively ends the claim.

Petrucelli relied on an asserted oral assurance from an unidentified Oklahoma official and on information from his process server that Oklahoma service was available. Those circumstances did not excuse the failure to verify whether Jake Diel was in good standing in Oklahoma or whether the Secretary was authorized to accept service.

Counsel also failed to follow up when the acknowledgment form included with the attempted service was never returned. A reasonably diligent lawyer would have investigated the missing acknowledgment rather than assume effective service from an unverified verbal assurance.

Third-party or process-server error, counsel's inadvertence, and half-hearted service efforts ordinarily do not establish good cause. Petrucelli also could have investigated Texas, where Jake Diel, later renamed Excel, had continuously conducted business.

Because the district court decided under former Rule 4(j), it correctly concluded that no good cause existed but did not have authority to consider a discretionary extension. The Third Circuit therefore affirmed the no-good-cause ruling and remanded solely for the district court to decide whether, despite the absence of good cause and with the limitations bar in mind, to allow additional time for service.

Negligence, strict liability, and misrepresentation each required a causal connection between Bohringer's alleged wrongful conduct and Petrucelli's injury. Bohringer made the rotor crusher, but Petrucelli was injured by the discharge conveyor, which was separated from the crusher by three independent components. The undisputed record showed no causal role for Bohringer's component.

A component manufacturer generally has no duty under Pennsylvania law to warn of dangers created by a finished product assembled by another entity. While a component maker can be liable when a danger tied to its component's intended incorporation is reasonably foreseeable, Bohringer could not reasonably be expected to foresee that the absence of alarms on its rotor crusher would cause an injury at a separately manufactured discharge conveyor.

Petrucelli's control-booth design theory also failed. He produced no evidence that Bohringer manufactured the booth, provided a means to attach it to the rotor crusher, selected its location, or controlled its design. The evidence instead showed that Jake Diel located control booths according to customer requirements and had used similar placements before it used Bohringer crushers.

The implied-warranty claims required proof that Bohringer's product was defective. Petrucelli did not establish either a defect in the rotor crusher or, for warranty of fitness for a particular purpose, reliance on Bohringer's skill or judgment. Summary judgment for Bohringer was therefore proper.

A motion to compel presupposes that the movant actually served discovery on the opposing party. Petrucelli never served his own interrogatories or document requests on Bohringer; his principal discovery effort was a short deposition of a Bohringer representative.

Excel had served discovery requests on Bohringer, but Petrucelli did not attempt to adopt them until roughly ten months later. There was no written stipulation permitting that modification of normal discovery procedures, as Rule 29 required.

Petrucelli waited more than two years after commencing the action to pursue discovery and filed his motion to compel only after Bohringer moved for summary judgment. Given that delay, the lack of direct requests, and the absence of the required agreement, the district court acted within its discretion in denying the motion.