Harold R. Clayton, Justice
This is an appeal from an order sustaining a plea of privilege. Appellant, Norvell Wilder Supply Company, filed this suit for declaratory judgment and breach of an insurance contract wherein appellant sought to establish that appellee, Employers Casualty Company, was obligated to defend appellant in an action for damages pending in the District Court of Oklahoma County, State of Oklahoma. Appellant seeks to maintain venue in Jefferson County under the provisions of TEX. REV. CIV. STAT. ANN. art. 1995, Subdivision 23 (1964). The trial court, in sustaining appellee's plea of privilege to be sued in Dallas County, the place of its residence, filed findings of fact and specifically found that all venue facts under Subdivision 23 were proven except "[t]hat the insurance policy at issue does not, as a matter of law, impose any obligation upon Defendant [appellee] to defend Plaintiff from the allegations made in the pleadings in the Oklahoma litigation."
The sole question before this court is whether appellant has proved a cause of action against appellee. If a cause of action has been proved, then the plea of privilege should have been overruled by the trial court.
In March of 1976, W.V. Harlow, Jr., filed a suit for damages against Beacon Supply Company and others in the District Court of Oklahoma County, State of Oklahoma. Prior to that time, appellant had acquired the Beacon Supply Company which thereafter became the Beacon Supply Division of Norvell Wilder Supply Company. At the time the Oklahoma suit was filed, appellant was the party defendant in such damage suit.
Appellee had issued a Comprehensive General Liability Insurance policy to Beacon for the time involved in the Oklahoma litigation. Timely demand was made upon appellee to assume the defense of the Oklahoma suit pursuant to the provisions of the insurance policy.
The policy contains the following provisions:
"The company will pay on behalf of the insured all sums which the insured shall become legally obligated to pay as damages because of Coverage A. bodily injury or Coverage B. property damage to which this insurance applies, caused by an occurrence, and the company shall have the right and duty to defend any suit against the insured seeking damages on account of such bodily or property damage, even if any of the allegations of the suit are groundless, false or fraudulent...."
The word "occurrence," as used in the above-quoted provision as to property damage, is defined in the policy as meaning "an accident, including continuous or repeated exposure to conditions, which results in bodily injury or property damage neither expected nor intended from the standpoint of the insured."
The appellee's duty to defend the Oklahoma suit is determined by the allegations of the petition when considered in the light of the policy provisions without reference to the truth or falsity of such allegations. Argonaut Southwest Insurance Company v. Maupin, 500 S.W.2d 633 (Tex. 1973); Heyden Newport Chemical Corporation v. Southern General Insurance Company, 387 S.W.2d 22 (Tex. 1965). Whether the insurer has the duty to defend does not depend upon the suit in fact being within the coverage, but it is determined by the allegation of liability within the coverage. Millers Mutual Fire Insurance Company of Texas, v. Texoma Directional Drilling Company, Inc., 622 S.W.2d 899 (Tex. Civ. App.--Fort worth 1981, no writ).
If the "allegations in the petition filed against an assured, when fairly and reasonably construed, state a cause of action covered by the policy" then the duty to defend arises. Sewer Constructors, Inc. v. Employers Casualty Co., 388 S.W.2d 20, 21 (Tex. Civ. App. -- Houston 1965, writ ref'd n.r.e.).
The material allegations as to Beacon in the second amended petition filed in the Oklahoma suit are that plaintiff's "undertook to construct a pipeline" for the purpose of connecting certain gas wells operated by them to lines operated by the purchasers of the gas. The fiber-glass pipe used in this undertaking was manufactured by defendant Kinetics and supplied by Beacon with certain fittings supplied and fabricated by Beacon.
Plaintiffs further alleged that they entered into a contract to purchase pipe from Beacon and a contract for laying the pipeline with defendant Williamson. Plaintiffs alleged that the defendants (including Beacon) "have committed certain tortious acts within this State (Oklahoma), have caused tortious injury in this State by the commission of acts or omissions...."
Plaintiffs alleged that they have been damaged as a result of "... negligence on the part of Defendant [Beacon] in one or more of the following particulars:
"1. [Beacon] breached its express... warranties... in that... the pipe, was defective and would not ...