Jesus Favala appeals the district court’s entry of judgment on a jury verdict in favor of Cumberland Engineering Company. We vacate the judgment and remand for a new trial.
I. BACKGROUND
Favala was injured in an accident that occurred during the course of his employment at Colver Leasing, Inc. While Favala was operating a “pelletizer,” (a machine that uses rapidly rotating blades to cut long strands of plastic into small pieces) Favala’s right hand became caught in the machine’s rollers and drawn into the rotating blades. He tried to use his left hand to free his right hand, but his left hand also became caught and drawn into the blades. Both hands were *989 injured, with the left hand suffering the greatest damage. 1
Favala sued his employer, Colver, and the pelletizer’s manufacturer, Cumberland Engineering Company (“Cumberland”). The suit alleged that Cumberland 2 was negligent for failing to attach certain safety devices and warnings to the machine. During the course of discovery, Favala propounded a series of interrogatories to Cumberland that were answered in April 1989 by Roy Gerstenberg. At the time, Gerstenberg bore the title of Vice President of Product Integrity. His response to the interrogatories indicated he could not answer the questions without first personally inspecting the machine.
On May 1, 1989, Favala served Cumberland notice of his intent to depose Gersten-berg. On May 31, Cumberland had Gersten-berg sign a confidentiality agreement that, in pertinent part, prohibited him from divulging “the trade secrets and proprietary, confidential, private or non-published information relating to the business, operation or financial affairs of the Company....” In September 1989, Cumberland fired Gerstenberg for reasons unrelated to this case, and he began a consulting business. Favala then retained Gerstenberg’s services. After several continuances, Favala took Gerstenberg’s deposition on May 18, 1990.
Approximately one month later, Cumberland filed a motion to bar Gerstenberg from testifying at trial, alleging that permitting his testimony would violate Cumberland’s attorney-client privilege and the confidentiality agreement. The motion averred that Ger-stenberg “took part in all defense and discovery activities, and received copies of all correspondence between counsel and defendant discussing defense strategy, plans and goals, and, in short, served as the agent of the corporate defendant in the confidential development of the defense of this matter with defense counsel.” Favala’s response included an affidavit from Gerstenberg in which he stated that his only communications with Cumberland’s attorney consisted of him providing facts and documents necessary to respond to discovery, and that had no knowledge about defense strategy, plans or goals. Cumberland’s reply included an affidavit from its attorney specifying the dates and methods of his communications with Gersten-berg and alleging that he “kept [Gersten-berg] fully informed of all facts, impressions, strategies and plans for the defense of [Cumberland], including the pending case of Favala v. Cumberland.”
The district court granted Cumberland’s motion because it believed there was “no way to protect against the use of confidential information and trial strategy discussions .... ” It also indicated that its decision rested to some extent on the confidentiality agreement Gerstenberg had signed. The case proceeded to trial, and the jury entered a verdict in Cumberland’s favor. Favala has appealed the verdict based on the district court’s decision to bar Gerstenberg’s testimony.
II. DISCUSSION
The parties agree that Illinois law governs the scope and application of the attorney-client privilege because Illinois law governs the claims and defenses involved in this diversity suit.
Barrett Indus. Trucks, Inc. v. Old Republic Ins. Co.,
A. The Existence of an Attorney-Client Relationship
The leading attorney-client case involving a corporation is
Consolidation Coal Co. v. Bucyrus-Erie Co.,
In the case at bar, the record does not support the conclusion that Gerstenberg was a member of the control group. Indeed, this appears to be a matter of some dispute, as the conflicting affidavits demonstrate. It was improper for the court to decide, based on these conflicting affidavits, that Cumberland carried its burden of proving Gersten-berg was a member of the control group. Moreover, even if the allegations in Cumberland’s motion and supporting affidavit are true, they do not demonstrate that Gersten-berg had decisionmaking authority with respect to this lawsuit.
B. The Existence of Privileged Information
Our next concern focuses on the dis-triet court’s conclusion that there was no way to allow Gerstenberg to testify and still protect privileged information. Assuming Ger-stenberg was a member of the control group, we do not believe this conclusion is in accordance with either the law or the facts.
“A witness is not the property of either party to a suit and simply because one party may have conferred with a witness and even paid him for his expert advice does not render him incompetent to testify for the other party.”
People v. Speck,
Thus, we conclude that Illinois law allowed Gerstenberg to testify so long as he did not divulge the substance or subject of his communications with Cumberland’s attorney. This conclusion about Illinois law leads us to our concern about the facts: at no time—not during the deposition, in motions or argument before the district court, or in the briefs filed with this court—has Cumberland specified what part of Gerstenberg’s testimony constitutes disclosure of attorney-client confidences. In fact, during oral argument, Cumberland’s counsel conceded that the testimony in Gerstenberg’s deposition did not cause any concern. In explaining why Cum *991 berland went to such lengths to bar Gersten-berg’s testimony, we were told that there was a concern that Gerstenberg might divulge confidential matters during the course of his testimony. This generalized fear was not a reason to bar the witness in either Speck or Claxton, and does not justify the complete barring of Gerstenberg’s testimony in this case.
C. Trade Secrets
At oral argument, Cumberland’s counsel conceded that Gerstenberg’s deposition did not contain any trade secrets. Our review of Gerstenberg’s deposition verifies this: Gerstenberg’s deposition consists of expert opinions based on questions and facts presented by Favala’s attorney. If Gerstenberg could testify at his deposition without violating the confidentiality agreement, then it would have been possible to do so at trial. The confidentiality agreement does not justify preventing Favala from calling Gerstenberg as a witness at trial.
D. Remedy
In deciding whether Favala is entitled to a new trial, we must determine what effect, if any, to attach to Favala’s failure to call Gerstenberg to the stand to testify or otherwise renew his resistance to Cumberland’s motion. Cumberland contends these failures constitute a waiver of these issues. We disagree. The majority of our cases indicate that “the law in this circuit is that an unsuccessful motion in limine does preserve the issue for appeal....”
Allison v. Ticor Title Ins. Co.,
Cumberland further contends Favala waived the issue by not accepting the court’s invitation to renew this issue. We have treated such invitations as an indication that the court’s ruling on the motion in limine is not final and is open to reconsideration; consequently, the failure to follow up on the invitation constitutes a waiver.
United States v. Hoyos,
Finally, we cannot agree with Cumberland’s contention that the error was harmless. Though Favala did utilize expert testimony, Cumberland argued to the jury that Favala’s engineer lacked experience in the plastics industry. Cumberland’s contention that engineers with this experience “are thick on the ground in Chicago” is neither supported by the record nor relevant. Favala was entitled to select his experts and elicit their testimony barring a legitimate reason to deny him his choices — and as we stated above, no such reason exists in this case.
III. CONCLUSION
The district court erred in barring all testimony from Gerstenberg because there was no showing the attorney-client privilege applied to Gerstenberg’s testimony and, even if it did, because the existence of the privilege would not have justified completely barring his testimony. The district court also erred in barring the testimony based on the confi *992 dentiality agreement because, by Cumberland’s concession, Gerstenberg’s testimony did not divulge confidential matters. We vacate the judgment and remand for further proceedings.
Notes
. We will not recount the extent of Favala's injuries because they are not germane to the issues on appeal and there is no dispute as to the origin or severity of his injuries.
. The suit against Colver was settled prior to trial and is not an issue in this appeal.
. Cumberland attempts to distinguish
Speck
by arguing the fingerprint expert was testifying about factual matters he had observed and not his opinions. Assuming the distinction is important (which we sincerely doubt), it is quite clear that testimony regarding fingerprint analysis is a matter of expert, opinion testimony.
See, e.g., Speck,
