This appeal arises from a suit involving the death of Reymundo Torres for which appellants contended appellee Caterpillar Industrial, Inc. (“Caterpillar”) was responsible under a strict product liability theory. A partial motion for summary judgment was granted in favor of Caterpillar with regard to appellants’ manufacturing defect and design defect claims, 1 and the jury found in favor of Caterpillar with respect to appellants’ failure to warn defect claim. In five points of error, appellants raise the following complaints contending the trial court erred by: (1) granting the partial summary judgment dismissing the design defect claim; (2) instructing the jury regarding Caterpillar’s agency relationship with its authorized dealers; (3) instructing the jury that Torres’ employer, Rymco, Inc. (“Rymeo”), was in default and negligent by falling to appear; (4) admitting the testimony of an improperly designated fact witness; and (5) accepting a jury verdict containing an irreconcilable conflict. The trial court’s judgment is affirmed in part and reversed in part.
FACTS
In May of 1989, Reymundo Torres was unloading containers from a light truck with a 1968 forklift manufactured by Caterpillar. *237 As he was backing the forklift out of the truck, the forklift fell between the loading doek and the back of the truck, killing Mr. Torres.
Torres was working for a warehouse that was owned and operated by Rymco, a non-subseribing employer under Texas workers’ compensation laws. Mr. De La Rosa, the president of Rymco, testified he purchased the forklift from a dealer in San Antonio, but he could not recall the name of the dealer, only that the agent worked in Laredo. The forklift was manufactured by Caterpillar; however, the overhead guard, which was standard equipment on forklifts delivered by Caterpillar to its dealers, was missing. The overhead guard was designed to protect the driver from falling debris rather than as a rollover protection device.
Appellants brought suit against both Rym-co and Caterpillar. Appellants claimed Rym-co’s negligence caused Mr. Torres’ injury while appellants’ claim against Caterpillar was for strict product liability. Prior to trial, a partial summary judgment was granted in favor of Caterpillar as to the following: (1) Caterpillar, Inc., who was not the manufacturing entity, was dismissed from the suit with prejudice; (2) all allegations with regard to a manufacturing defect were dismissed; and (8) all allegations with regard to a design defect in the original overhead guard were dismissed. At trial, Rymco failed to appear and defend against appellants’ claims; however, the case was tried before a jury as to appellants’ claim against Caterpillar for a failure to warn or marketing defect. 2
The jury failed to find that any marketing defect was a producing cause of Mr. Torres’ death. The jury found the following percentage causation: (1) Mr. Torres — 45%; (2) Rymco — 50%; and (3) Caterpillar — 5%. The jury awarded a total of $425,000 in damages, and the trial court entered a judgment against Rymco for the full amount. 3 The trial court’s judgment also reflected that appellants took nothing by their suit against Caterpillar.
ARGUMENTS ON APPEAL
In five points of error, appellants raise the following complaints contending the trial court erred by: (1) granting the partial summary judgment dismissing the design defect claim; (2) instructing the jury regarding Caterpillar’s agency relationship with its authorized dealers; (3) instructing the jury that Rymco was in default and negligent by failing to appear; (4) admitting the testimony of an improperly designated fact witness; and (5) accepting a jury verdict containing an irreconcilable conflict. We address the points of error in the order raised by appellants.
1. Summary Judgment
In their first point of error, appellants contend that the trial court erred in rendering the partial summary judgment dismissing the design defect allegation. Appellants contend that their expert’s affidavit raised a fact issue as to whether the overhead guard was defectively designed and could have been designed as a safer more effective rollover protective structure. Caterpillar counters that appellants’ argument is raised for the first time on appeal since the expert affidavit presented by appellants to the trial court did not criticize the removability of the overhead guard.
In its motion for summary judgment, Caterpillar asserted the overhead guard was manufactured and delivered as standard equipment and was removed by unidentified third parties who were not under the control of Caterpillar. In support of this assertion, Caterpillar presented the affidavit of Martin T. Robertson, a staff engineer, who stated *238 the forklift was initially sold and shipped to an authorized dealer in Cleveland, Ohio, who subsequently sold it to Republic Supply Co. in Northeastern, Ohio. Mr. Robertson further stated in his affidavit that the forklift was sold with the overhead guard as standard equipment, the overhead guard complied with A.S.A. B56.1-1959, and that the removal of the overhead guard is permissible in limited circumstances under O.S.H.A. regulations. 4 Finally, Mr. Robertson stated Caterpillar never regained possession of or exercised control over the forklift after initial delivery nor did it ever redesign the overhead guard.
Caterpillar also presented the excerpted deposition testimony of Mr. De La Rosa, the president of Rymco, who provided the following information regarding his purchase of the forklift:
Q. Did you buy the forklift involved in the accident on May 17, 1989 used or new?
A. Used.
Q. And who did you buy it from?
A. Caterpillar.
Q. A dealer?
A. In San Antonio.
Q. Do you remember the name of the dealer there?
A. The agent worked in Laredo. I don’t recall the name right now.
Q. When did you buy it?
A. Fifteen years ago — I don’t know.
In their response to Caterpillar’s motion for summary judgment, appellants specified the forklift had the following defects: (1) the overhead guard, which was standard safety equipment on the forklift as manufactured, was removed before it was marketed and/or sold to Rymco by an agent, employee or representative operating under the control of Caterpillar; (2) the forklift contained no warnings regarding the danger in operating the forklift without the overhead guard; and (3) the overhead guard was defective in merely providing “falling object protection” and not “rollover protection.” 5 Appellants presented the affidavit of Dr. Jeffrey Ketch-man in support of their contention that genuine issues of material fact were raised as to whether each of these defects caused or contributed to Mr. Torres’ death.
Dr. Ketehman stated in his affidavit that if an overhead guard had been in place at the time of the incident, “it would have provided a significant measure of protection such that the severity of Mr. Torres’ injuries would have been significantly reduced (along with the probability of his death).” Dr. Ketehman further stated “another defect of the subject forklift is defective warnings and instructions,” and the absence of such safety warnings and instructions to alert the user that the forklift was initially designed with an overhead guard was another contributing factor that caused Mr. Torres’ injuries and death. Finally, Dr. Ketehman concluded the forklift should have been designed with a rollover protective structure, and the absence of such a structure rendered the forklift design defective, contributing directly to Mr. Torres injuries and death.
As previously noted, the trial court granted a partial summary judgment dismissing any allegation with regard to either a manufacturing defect or a design defect in the original overhead guard. Appellants’ contention regarding the failure to warn defect was tried to the jury; therefore, the summary judgment only affected appellants’ contentions regarding the absence of the overhead *239 guard and the absence of a rollover protective structure.
a. Standard of Review
The standard for reviewing a motion for summary judgment has been clearly established. The movant for summary judgment is first required to disprove at least one of the essential elements of each of the plaintiffs causes of action in order to prevail on summary judgment.
Lear Siegler, Inc. v. Perez,
Texas law recognizes summary judgment to be a harsh remedy requiring strict construction.
Garcia v. John Hancock Variable Life Ins. Co.,
b. Rollover Protection
A product may be held to be unreasonably dangerous based on a defect in manufacturing, design or marketing.
Caterpillar, Inc. v. Shears,
In the instant case, appellants asserted the forklift was defectively designed by merely providing falling object protection and not rollover protection. In response to the motion for summary judgment, appellants produced Dr. Ketchman’s affidavit wherein he stated that the failure to equip the forklift with a rollover protective structure was a design defect. Caterpillar did not controvert this affidavit. Although appellants would be required to produce evidence at trial that the forklift could have been equipped with a rollover protective structure without destroying its utility, we hold that Dr. Ketchman’s affidavit was sufficient to raise a question of fact, thereby entitling the appellants to present this issue to a jury.
See Caterpillar, Inc. v. Shears,
c.Removal of Overhead Guard
Appellants presented no summary judgment proof to counter the affidavit testimony of Martin T. Robertson, a staff engineer, who stated the overhead guard complied with A.S.A. B56.1-1959, and that the removal of the overhead guard is permissible in limited circumstances under O.S.H.A. regulations.
See also Caterpillar, Inc. v. Shears,
*240 The second issue presented with respect to the removal of the overhead guard is whether Caterpillar can be held liable under strict product liability for the sale of the forklift to Rymco without the overhead guard. Caterpillar asserted unauthorized third persons who were not under its control removed the guard. However, the only evidence as to the identity of the person or entity who sold Rymco the forklift was the deposition testimony of Rymeo’s president, Mr. De La Rosa. Mr. De La Rosa stated he purchased the forklift in approximately 1974 from a Caterpillar dealer in San Antonio through an agent in Laredo.
Resolving all doubt in favor of the non-movant, appellants contend we must assume from the evidence that the dealer from which Rymco purchased the forklift was one of Caterpillar’s independent authorized dealers. We. note that Caterpillar could have countered Mr. De La Rosa’s testimony by presenting evidence from its authorized dealers that Rymco did not purchase a forklift from them. Since its authorized dealers stand in a special relation to Caterpillar, we may infer from Caterpillar’s failure to present such evidence that the dealers testimony would have been unfavorable to Caterpillar. See
John Deere Co. v. May,
Caterpillar also argued in its summary judgment motion that if we assume the forklift was purchased from an authorized dealer, there would be no post-sale strict liability created since the overhead guard was not claimed to be defective at the time of sale but simply not re-installed. However, we believe the issue is whether Caterpillar can be held liable under strict product liability if an authorized dealer reacquired a used forklift and sold it without the overhead guard eight years after the initial delivery of the forklift by Caterpillar.
Section 402A of the Restatement (Second) of Torts imposes strict product liability only in those instances where the product is defective when sold and it reaches the user without substantial change. Restatement (Second) of Torts § 402A (1965);
see also McKisson v. Sales Affiliates, Inc.,
In
Bell Helicopter Co. v. Bradshaw,
a helicopter manufacturer was sued for injuries sustained when one of the tail rotor blades broke off causing the helicopter to crash.
In
Dion v. Ford Motor Co.,
a tractor manufacturer was sued when a tractor which was manufactured in 1950 rolled over on its operator in 1982.
Whether a post-sale duty exists under these facts is a question of law.
Dion,
2. Instruction as to Agency Relationship
In their second point of error, appellants contend the trial court erroneously instructed the jury to disregard Caterpillar’s agency relationship with its authorized dealers. Caterpillar responds the instruction was proper because the testimony of Mr. De La Rosa, to which Caterpillar contends the instruction relates, was irrelevant to any issue in the case. The instruction at issue is the following:
You are instructed that the forklift in question left Caterpillar Industrial Inc.’s factory with an over head guard. You are further instructed that the seller of the used forklift is not a party to this law suit, and any evidence concerning the sale of the used fork lift without an overhead guard to Rymco by the used equipment seller shall be disregarded.
Explanatory instructions are proper when they aid the jury in answering the submitted issues.
Jobe v. Penske Truck Leasing Corp.,
The only issue submitted to the jury with regard to Caterpillar’s liability was whether there was a defect in the marketing of the forklift at the time it left the possession of Caterpillar in 1968. Therefore, evidence regarding the transfer of the forklift to Rymco without the overhead guard was not relevant to the submitted issue, and we find the instruction would clearly aid the jury in focusing on the evidence relevant to the timing at issue.
3. Instruction Regarding Defaulting Party and Comparative Negligence Issue
Appellants contend in their third point of error that the trial court’s instruction regarding Rymco’s liability as a defaulting party was improper. The instruction submitted by the trial court read as follows:
You are instructed that Rymco, Inc.’s negligence was a proximate cause of the injury, death or occurrence in question.
Appellants also contend that it was error for the trial court to submit an issue on Mr. Torres’ contributory negligence.
Whether a trial court errs in submitting an instruction is reviewed on appeal under an abuse of discretion standard.
Perez v. Weingarten Realty Investors,
Contributory negligence and comparative causation are appropriate issues for jury submission in a strict liability case.
See Duncan v. Cessna Aircraft Co.,
4. Testimony of Improperly Designated Fact Witness
In their fourth point of error, appellants argue that the trial court erroneously permitted Hector Flores, an improperly designated fact witness, to testify at trial. Caterpillar counters that there was good cause for the late discovery information provided regarding Flores and, in any event, Flores’ testimony was cumulative of other evidence.
In their answers to interrogatories filed November 16,1990, appellants first designated Flores as a fact witness providing an address and phone number for him and indicating that although he was at the Rymco warehouse the day of the accident, he was not a witness and was not contacted. On December 18, 1993, Caterpillar listed Flores in its list of trial witnesses as a fact witness with an address of “Rymco, Inc., Laredo, Texas.” On December 20, 1993, appellants also listed Flores in their list of trial witnesses with an address of “Rymco Storage and Forwarding Agency, Inc., 2016 Lincoln, Laredo, Texas.” On March 16, 1994, Caterpillar attempted to have Flores served with a trial subpoena, and the officer filed his return of service with the court on March 21, 1994. On Friday, March 24, 1994 at 4:04 p.m., Caterpillar provided appellants with its amended list of trial witnesses, which included a current phone number for Flores. The case was called for trial on March 28, 1994.
Parties have an affirmative duty to supplement discovery answers, including supplementation necessary to supply addresses for individuals identified by a party as a fact witness in response to a discovery request.
Boothe v. Hausler,
One factor a trial court may consider in determining whether there has been a showing of good cause is whether the witness was designated by both parties.
Aluminum Co. of America v. Bullock,
In the instant case, both parties designated Flores as a fact witness; however, neither party had a current address or phone number. Appellants presented a letter at the “good cause” hearing dated March 16, 1994, wherein Caterpillar was requesting that a subpoena be issued for Flores. That letter contained Flores’ current work address and phone number. Although the phone number *244 was later added to the amended trial list on March 24, 1994, the current address was not added. It was undisputed that appellants were able to contact Flores before trial and that Caterpillar agreed to permit appellants to take Ms deposition before he testified. Appellants contended that there was insufficient time to prepare for Flores’ testimony because it had “changed since they’ve since spoken to Caterpillar.” Caterpillar asserts that tMs is another way of saying appellants did not like what Flores had to say.
Even were we to conclude that the trial court erred in admitting Flores’ testimony, the error would not require reversal unless it resulted in harm to appellants or was reasonably calculated to cause and probably did cause the rendition of an improper judgment.
Alvarado,
5. Irreconcilable Conflict in Jury Finding
Appellants raise a fifth point of error eon-tendmg the trial court erred M aeceptmg the jury verdict due to the conflict between the liability and percentage of negligence findings. Apart from the pomt of error recital, appellants’ brief contained no argument regarding tMs point of error.
Caterpillar first contends that the appellants have waived tMs point of error m failmg to brief the pomt. TMs court’s decision m
Tatum v. Liner,
Appellants did not raise their complaint regardmg the mconsistency m the jury’s answers until they filed their motion for mistrial on May 3, 1994. The jury returned its verdict on April 1,1994, and judgment was entered on August 22, 1994. No mention is made m the judgment regardmg the conflict between the no liability finding as to Caterpillar but the apportionment to Caterpillar of 5% causation. The general rule provides that no complaint regardmg a conflict m the jury answers may be raised on appeal uMess an objection is raised before the jury is discharged.
See, e.g., Ciba-Geigy Corp. v. Stephens,
Finally, in the event of a perceived conflict between a liability and percentage causation finding, the jury’s response to the liability issue is controlling.
American Jet, Inc. v. Leyendecker,
CONCLUSION
Appellants’ first point of error is sustained, and the summary judgment in favor of Caterpillar with respect to appellants’ allegation of design defect based on the overhead guard being designed to protect the driver from falling debris rather than as a rollover protection device is reversed, and that cause is remanded to the trial court for trial. Appellants’ remaining five points of error are overruled, and the remainder of the judgment is affirmed.
Notes
. The partial summary judgment was granted by the Honorable Manuel Flores. The Honorable Ron Can: presided over the jury trial.
. Within thirty days before trial, appellants sought to amend their pleadings to assert negligence and gross negligence claims against Caterpillar. The trial judge struck these pleadings and stated the issue to be tried was the failure to warn defect.
. Since Rymco was a non-subscribing employer, contributory negligence was not a defense, and. therefore, the trial court properly disregarded the percentage causation the jury attributed to Mr. Torres’ negligence in awarding damages against Rymco. Acts 1917, p. 269 (Tex.Rev.Civ. Stat. Ann. art. 8306 § 1, 4 (Vernon 1967)) (repealed 1991) (current version Tex. Labor Code Ann. § 406.033 (Vernon Supp.1996)).
. A.S.A.B56.1-1959 is the American Standard Safety Code for Powered Industrial Trucks. Section 1910.178(m)(9) of the regulations promulgated by the Occupational Safety and Health Administration expressly provides:
An overhead guard shall be used as protection against falling objects. It should be noted that an overhead guard is intended to offer protection from the impact of small packages, boxes, bagged materials, etc., representative of the job application, but not to withstand the impact of a falling capacity load.
29 C.F.R. § 1910.178(m)(9) (1984)(admitted at trial as Caterpillar Trial Exhibit # 13);
see also Caterpillar, Inc. v. Shears,
. Appellants’ response specifically references the defect in design based on the absence of a rollover protective structure which also is addressed in Dr. Ketchman’s affidavit. Caterpillar’s contention that this is a new theory is without merit.
. We note that in order to prevail at trial on the design defect claim relating to the absence of rollover protection, appellants will be required to prove that a rollover protection design would not
*240
prevent the forklift from performing the same tasks it could preform under its existing design or, in other words, a rollover protection design would not destroy the forklift’s utility.
See Caterpillar, Inc. v. Shears,
. With respect to this second distinction, it should be noted that the replacement program in the
Bell Helicopter
case was not undertaken until after the accident giving rise to the suit on appeal.
