NOT TO BE PUBLISHED IN THE OFFICIAL REPORTS

TURNER, P. J.

I. INTRODUCTION

Defendants, Fountain Valley Regional Hospital (the hospital), Deborah Keel, Tenet Healthcare Corp., Cotkin & Collins (the law firm), Kevin A. Duffis, Dr. Veeraiah Chundu, OC Neonatal Group, Inc. and Dr. Shahid Nazir, appeal from the October 25, 2010 order denying their renewed petition to compel arbitration. Dr. Chundu, OC Neonatal Group and Dr. Nazir are not signatories to a written arbitration agreement. But, defendants argue equitable estoppel principles require arbitration of the claims asserted by plaintiffs, Dr. Jacob Sweidan and Pediatrics & Neonatology Medical Group of Orange County, Inc. We disagree and affirm the trial court's denial of defendants' renewed petition to compel arbitration.

II. BACKGROUND

A. First Amended Complaint

Plaintiffs' first amended complaint alleges in 2008, the hospital entered into negotiations with plaintiffs. The purpose of the negotiation was to have Pediatrics & Neonatology Medical Group of Orange County replace Pediatrix Medical Group of California (Pediatrix Group) as the exclusive provider of physician services at the hospital's neonatal intensive care unit. Ms. Keel, the hospital's chief executive officer, wanted Dr. Chundu, the Pediatrix Group medical director, to remain working at the hospital's neonatal intensive care unit. This was because Dr. Chundu had been at the hospital for a long time. In early 2009, plaintiffs engaged Mr. Duffis and the law firm to provide a legal opinion. The opinion was to evaluate the non-competition and confidential information provisions of Dr. Chundu's employment agreement with Pediatrix Group. Mr. Duffis and his law firm also prepared service contracts that plaintiffs provided to physicians, including Dr. Nazir, who were to staff the hospital's neonatal intensive care unit.

On June 10, 2009, the hospital and Dr. Sweidan, on behalf of Pediatrics & Neonatology Medical Group, signed an agreement (the coverage agreement). The coverage agreement granted Pediatrics & Neonatology Medical Group the exclusive right to provide physician services in the hospital's neonatal intensive care unit. The coverage agreement required Pediatrics & Neonatology Medical Group to hire a sufficient number of physicians, as determined by the hospital, to staff the neonatal intensive care unit. The coverage agreement also required Pediatrics & Neonatology Medical Group to appoint a medical director to administer the neonatal intensive care unit subject to the hospital's prior approval.

Dr. Chundu agreed to work for plaintiffs. The first amended complaint describes the circumstances of their agreement: "[Dr. Sweidan] met initially with [Dr. Chundu] to see if they could work out a mutually beneficial employment relationship. [Dr. Chundu] and [Dr. Sweidan] discussed the provisions of [Dr. Chundu's] employment agreement with Pediatrix [Group] which included a non-competition provision. A salary and bonus arrangement were discussed with the bonus determined by the profits of the [hospital's neonatal intensive care] operations. [¶] . . . [Dr. Sweidan] told [Dr. Chundu] that the only way he would proceed would be with an understanding that his sharing of confidential and proprietary information about the anticipated business model for the [neonatal intensive care unit] was to be used exclusively for [Dr. Chundu's] employment arrangement discussions. [¶] [Dr. Chundu] stated that he had no prior experience being a manager of a medical practice and that while employed for many years as a Pediatrix [Group] employee he had only limited access to the budget or profitability numbers for the [hospital's neonatal intensive care unit]. [Dr. Chundu] stated that he would gladly work for plaintiffs and represented and acknowledged that he required plaintiffs' substantial and valuable business expertise and would keep confidential all of the proprietary and confidential information that he would be provided."

Plaintiffs further allege Dr. Chundu, who had worked at the hospital for a "long time," initially agreed to the terms of an employment agreement. But, plaintiffs alleged Dr. Chundu later materially changed the terms of the employment agreement by demanding a greater salary and a higher profit sharing percentage. The first amended complaint alleges Ms. Keel supported Dr. Chundu's efforts to "wrest the [c]overage [a]greement" from plaintiffs in return for patient referrals from him.

Mr. Duffis allegedly aided Dr. Chundu by advising plaintiffs that it was in their best interest to assign the coverage agreement. The coverage agreement was to be assigned to Dr. Chundu and his wholly-owned corporation, OC Neonatal Group, because Ms. Keel and the hospital had decided not to "work" with plaintiffs. Dr. Chundu and Mr. Duffis allegedly informed Shawn Dewars, a hospital employee, that plaintiffs had assigned the coverage agreement to Dr. Chundu and OC Neonatal Group, even though it was not assignable. Plaintiffs informed Mr. Dewars that: Mr. Duffis's statements were untrue; the parties were expected to live up to the terms of the coverage agreement; and they had already entered into physician service contracts in reliance on the coverage agreement.

On July 24, 2009, Ms. Keel allegedly met with Dr. Chundu and the doctors who had entered into a physician services contract with plaintiffs. Ms. Keel allegedly told these physicians that the coverage agreement would be terminated and they had to end their contract with plaintiffs. According to Ms. Keel, these physicians were to sign contracts with Dr. Chundu and OC Neonatal Group if they wanted to work at the hospital's neonatal intensive care unit. After the meeting, Dr. Glenn Ginoza and Dr. Nadal Machhor allegedly sent letters to the hospital claiming their physician service contracts with plaintiffs were not effective. Ms. Keel allegedly used these two physician letters as a basis for cancelling the coverage agreement in a July 24, 2009 letter she sent to plaintiffs.

The first amended complaint contains 11 causes of action. In the first cause of action, plaintiffs sued Dr. Chundu, Mr. Duffis, the law firm and Dr. Nazir for fiduciary duty breach. In the second cause of action for constructive fraud, plaintiffs sued Dr. Chundu, Mr. Duffis, the law firm and Dr. Nazir. In the third cause of action, Pediatrics & Neonatal Medical Group sued the hospital for contract breach. In the fourth cause of action, Pediatrics & Neonatal Medical Group sued Dr. Chundu, Dr. Nazir and OC Neonatal Group for interference with the coverage agreement. Also, Pediatrics & Neonatal Medical Group sued the hospital, Ms. Keel and Tenet Healthcare Corp. in the fourth cause of action for interference with the physician service contracts. In the fifth cause of action, Pediatrics & Neonatal Medical Group sued Dr. Chundu, Dr. Nazir and OC Neonatal Group for prospective economic advantage interference. In the sixth cause of action, plaintiffs sued the hospital and Tenet Healthcare Corp. for failing to supervise Ms. Keel. In the seventh cause of action, plaintiffs sued Mr. Duffis and the law firm for legal malpractice. In the eighth cause of action, plaintiffs sought an accounting from Dr. Chundu, Dr. Nazir and OC Neonatal Group. In the ninth cause of action, plaintiffs sued Dr. Chundu, Dr. Nazir and OC Neonatal Group for defamation. In the ninth cause of action, plaintiffs sued Dr. Chundu, Dr. Nazir and OC Neonatal Group for unfair competition. In the eleventh cause of action, plaintiffs sued defendants for tort of another. Plaintiffs subsequently dismissed their tort of another cause of action against all defendants.

B. The Two Petitions To Compel Arbitration And The Summary Adjudication Motion

On September 9, 2009, the hospital, Ms. Keel and Tenet Healthcare Corp. filed a petition to compel arbitration under the coverage agreement. On September 11, 2009, the law firm and Robert Wilson filed a petition to compel arbitration under the fee agreement. The fee agreement contains an arbitration clause. On September 16, 2009, Mr. Duffis joined in his law firm's petition to compel arbitration under the fee agreement. On November 4, 2009, Dr. Chundu, OC Neonatal Group and Dr. Nazir filed a petition to compel arbitration. In support of their petition to compel arbitration, they attached draft physician contract agreements between Pediatrics & Neonatology Medical Group, Dr. Chundu and Dr. Nazir. They also attached a draft joint agreement between plaintiffs and Dr. Chundu. All three proposed agreements contained arbitration provisions. Dr. Chundu, OC Neonatal Group and Dr. Nazir argued the arbitration clauses in the draft agreements should be enforced under equitable estoppel principles because plaintiffs were trying to enforce the terms of those draft contracts.

The trial court ruled: plaintiffs had enforceable arbitration agreements with the law firm, Mr. Duffis, the hospital, Tenet Healthcare and Ms. Keel; Ms. Keel and Tenet Healthcare could enforce the arbitration provision in the coverage agreement as the hospital's agents; and Mr. Duffis could enforce the arbitration provision in the fee agreement as the law firm's agent. The trial court exercised its discretion under Code of Civil Procedure section 1281.2, subdivision (c) and denied all of the petitions to compel arbitration. The trial court ruled Dr. Chundu and Dr. Nazir's actions were so intertwined with those of the other defendants that arbitration would likely result in conflicting rulings. On December 9, 2009, the trial court denied the petition to compel arbitration of OC Neonatal Group, Inc., Dr. Chundu and Dr. Nazir. The trial court ruled that OC Neonatal Group could not compel arbitration because there was no written agreement with plaintiffs. The trial court declined to enforce the arbitration clauses in the draft agreements because plaintiffs asserted causes of actions based on oral agreements with Dr. Chundu and Dr. Nazir. The trial court found there was no evidence the terms of the oral and written agreements were the same.

On May 25, 2010, the hospital, Tenet Healthcare and Ms. Keel filed a summary adjudication motion as to Pediatrics & Neonatal Medical Group's fourth cause of action for interference with the physician service contracts. In opposition, plaintiffs argued that Dr. Chundu, acting as the hospital's agent, interfered with Pediatrics & Neonatology Medical Group's agreements with the physicians who would staff the neonatal intensive care unit. The summary adjudication motion was denied. The trial court ruled there were triable issues as to whether: Pediatrics & Neonatal Medical Group had an oral contract with Dr. Nazir; Dr. Chundu interfered with the oral contract; and Dr. Chundu acted as the hospital's agent.

On August 12, 2010, Dr. Sweidan was deposed and he testified as follows. Dr. Sweiden discussed the draft physician services agreement with Dr. Nazir. It was likely that Dr. Sweidan showed Dr. Nazir the draft physician services agreement which contained an arbitration clause. During the meeting, Dr. Nazir said the draft physician services agreement was fine. Dr. Nazir started working for Dr. Sweidan after their conversation.

On August 23, 2010, the hospital, Tenet Healthcare Corp. and Ms. Keel filed a renewed petition to compel arbitration based on plaintiffs' assertion as to Dr. Chundu's agency status and Dr. Sweidan's deposition testimony. All other defendants joined in the renewed petition to compel arbitration. On October 25, 2010, the trial court denied the renewed petition to compel arbitration. The trial court found: Dr. Chundu and Ms. Keel consistently denied the existence of an agency relationship with the hospital; thus, defendants failed to meet their burden of showing the existence of an enforceable arbitration agreement. The trial court also found there was insufficient evidence to support an inference that Dr. Nazir agreed to an arbitration provision in connection with an oral contract to perform services for plaintiffs at the hospital. The trial court ruled, "[Dr.] Nazir has consistently contended that the written agreement to work for [Dr.] Sweidan at Fountain Valley hospital did not go into effect, as he revoked his acceptance of the agreement before he received an executed copy from [Dr.] Sweidan and before that agreement went into effect." The trial court ruled defendants could not rely on equitable estoppel principles because they denied the existence of the predicate facts necessary to conclude that the arbitration agreements covered Dr. Chundu, OC Neonatal Group and Dr. Nazir.

III. DISCUSSION

A. Overview

A trial court must order arbitration when the party proves the existence of a valid written agreement to arbitrate the dispute. (Laswell v. AG Seal Beach, LLC (2010) 189 Cal.App.4th 1399, 1404-1405; Garrison v. Superior Court (2005) 132 Cal.App.4th 253, 263.) Subject to three exceptions, one of which we discuss in the next paragraph, Code of Civil Procedure section 1281.2, provides: "On petition of a party to an arbitration agreement alleging the existence of a written agreement to arbitrate a controversy and that a party thereto refuses to arbitrate such controversy, the court shall order the petitioner and the respondent to arbitrate the controversy if it determines that an agreement to arbitrate the controversy exists . . . ." Our Supreme Court has held, "The petitioner bears the burden of proving the existence of a valid arbitration agreement by the preponderance of the evidence, and a party opposing the petition bears the burden of proving by a preponderance of the evidence any fact necessary to its defense." (Engalla v. Permanente Medical Group, Inc. (1997) 15 Cal.4th 951, 972; accord Brodke v. Alphatec Spine Inc. (2008) 160 Cal.App.4th1569, 1575 ["In seeking enforcement of the contract, defendants have the burden under section 1281.2 to allege the existence of a written agreement to arbitrate"].) A nonsignatory seeking to enforce an arbitration provision against a signatory bears the burden of establishing he or she is a party to the arbitration provision covering the dispute. (Jones v. Jacobson (2011) 195 Cal.App.4th 1, 15.)

The Court of Appeal has explained one of the exceptions to the duty to arbitrate: "One of the limited exceptions to the enforcement of contractual arbitration provisions is where `[a] party to the arbitration agreement is also a party to a pending court action or special proceeding with a third party, arising out of the same transaction or series of related transactions and there is a possibility of conflicting rulings on a common issue of law or fact.'" (Laswell v. AG Seal Beach, LLC, supra, 189 Cal.App.4th at p. 1405, quoting Code Civ. Proc. § 1281.2, subd. (c).) This exception applies when a controversy also affects claims by or against other parties not bound by the arbitration agreement. (Cronus Investments, Inc. v. Concierge Services (2005) 35 Cal.4th 376, 393; Laswell v. AG Seal Beach, LLC, supra, 189 Cal.App.4th at p. 1405.) The Court of Appeal has explained, "The exception thus does not apply when all defendants, including a nonsignatory to the arbitration agreement, have the right to enforce the arbitration provision against a signatory plaintiff." (Laswell v. AG Seal Beach, LLC, supra, 189 Cal.App.4th at p. 1405; Molecular Analytical Systems v. Ciphergen Biosystems, Inc. (2010) 186 Cal.App.4th 696, 709.)

B. Standard of Review

If the trial court's ruling is based on a decision of law, we conduct a de novo review. (Laswell v. AG Seal Beach, LLC, supra, 189 Cal.App.4th at p. 1406; Robertson v. Health Net of California, Inc. (2005) 132 Cal.App.4th 1419, 1425.) However, if the trial court's denial of a motion to compel arbitration is based on a decision of fact, we apply the substantial evidence standard. (Laswell v. AG Seal Beach, LLC, supra, 189 Cal.App.4th at p. 1406; Robertson v. Health Net of California, Inc., supra, 132 Cal.App.4th at p. 1425.) We accept the trial court's resolution of disputed facts when supported by substantial evidence. (Jones v. Jacobson, supra, 195 Cal.App.4th at p. 12; Engineers & Architects Assn. v. Community Development Dept. (1994) 30 Cal.App.4th 644, 653.) The Court of Appeal has held: "We also must presume the court found every fact and drew every permissible inference necessary to support its judgment and order, and we must defer to the court's determination of credibility of the witnesses and the weight of evidence in resolving such disputed facts." (Jones v. Jacobson, supra, 195 Cal.App.4th at p. 12; Engineers & Architects Assn. v. Community Development Dept., supra, 30 Cal.App.4th at p. 653.)

Whether a defendant is in fact a third party for purposes of Code of Civil Procedure section 1281.2, subdivision (c) is a matter of law subject to de novo review. (Laswell v. AG Seal Beach, LLC, supra, 189 Cal.App.4th at p. 1406; Rowe v. Exline (2007) 153 Cal.App.4th 1276, 1283.) But if the third-party exception applies, the trial court's discretionary decision as to whether to stay or deny arbitration is subject to the abuse of discretion standard of review. (Laswell v. AG Seal Beach, LLC, supra, 189 Cal.App.4th at p. 1406; Molecular Analytical Systems v. Ciphergen Biosystems, Inc., supra, 186 Cal.App.4th at p. 708.)

C. Equitable Estoppel

Equitable estoppel principles provide exception to the general rule that a nonsignatory to an agreement cannot be compelled to arbitrate. (JSM Tuscany, LLC v. Superior Court (2011) 193 Cal.App.4th 1222, 1236-1237; Westra v. Marcus & Millichap Real Estate Investment Brokerage Co., Inc. (2005) 129 Cal.App.4th 759, 763.) Under equitable estoppel, as applied in "both federal and California decisional authority, a nonsignatory defendant may invoke an arbitration clause to compel a signatory plaintiff to arbitrate its claims when the causes of action against the nonsignatory are `intimately founded in and intertwined' with the underlying contract obligations." (Boucher v. Alliance Title Co., Inc. (2005) 127 Cal.App.4th 262, 271; accord JSM Tuscany, LLC v. Superior Court, supra, 193 Cal.App.4th at p. 1237.) The equitable estoppel doctrine applies when a party has signed an agreement to arbitrate but attempts to avoid arbitration by suing nonsignatory defendants for claims that are "`"based on the same facts and are inherently inseparable"'" from arbitrable claims against signatory parties. (Turtle Ridge Media Group, Inc. v. Pacific Bell Directory (2006) 140 Cal.App.4th 828, 833, quoting Metaclad Corp. v. Ventana Environmental Organizational Partnership (2003) 109 Cal.App.4th 1705, 1713-1714.)

For equitable estoppel principles to apply, plaintiffs' claims against the nonsignatory "`must be dependent upon, or founded in and inextricably intertwined with, the underlying contractual obligations'" of the contract containing the arbitration clause. (JSM Tuscany, LLC v. Superior Court, supra, 193 Cal.App.4th at p. 1238; Goldman v. KPMG, LLP (2009) 173 Cal.App.4th 209, 217-218.) The focus is on the nature of the claims asserted by the plaintiff against the nonsignatory defendant. (JSM Tuscany, LLC v. Superior Court, supra, 193 Cal.App.4th at pp. 1238-1239; Boucher v. Alliance Title Co., Inc., supra, 127 Cal.App.4th at p. 272.) In conducting equitable estoppel review, we examine the facts alleged in the operative complaint. (JSM Tuscany, LLC v. Superior Court, supra, 193 Cal.App.4th at p. 1239; Goldman v. KPMG, LLP, supra, 173 Cal.App.4th at pp. 229-230.)

Defendants argue equitable estoppel principles are applicable because all of plaintiffs' claims, including those asserted against the nonsignatory defendants, Dr. Chundu, OC Neonatal Group and Dr. Nazir, rely on the coverage agreement. Plaintiffs allege claims against Dr. Chundu, OC Neonatal Group and Dr. Nazir for: fiduciary duty breach; constructive fraud; interference with the coverage agreement and prospective economic advantage; accounting; defamation and /slander per se; and unfair competition. The claims for interference with the coverage agreement and prospective economic advantage rely on the coverage agreement. But, not all of plaintiffs' claims against the nonsignatory defendants are dependent upon, or inextricably bound up with, the coverage agreement. Plaintiffs' claims for fiduciary duty breach, constructive fraud and accounting against Dr. Chundu and OC Neonatal Group are premised on Dr. Chundu's alleged possession of plaintiffs' confidential and proprietary information. Plaintiffs' fiduciary duty breach, constructive fraud and accounting claims against Dr. Nazir are based on the alleged obligations he owed them as an employee. Likewise, the defamation and slander per se claims are not dependent upon, or inextricably bound up with, the obligations imposed by the coverage agreement. In addition, plaintiffs' unfair competition cause of action, which alleges violations of the federal anti-kickback law is not dependent upon, or inextricably bound up with, the obligations imposed by the coverage agreement. Thus, equitable estoppel principles are not controlling.

Defendants also contend Dr. Chundu, a nonsignatory defendant, may enforce the coverage agreement's arbitration provision because plaintiffs are equitably estopped from denying his agency status. They argue that the estoppel arises because plaintiffs relied on his status as an agent having asserted it in their successful summary adjudication opposition. However, both Ms. Keel and Dr. Chundu deny he was the hospital's agent. Thus, substantial evidence supports the trial court's ruling that no valid arbitration agreement between Dr. Chundu and plaintiffs exists.

D. Oral Arbitration Agreement

An oral arbitration agreement is ordinarily unenforceable. (Magness Petroleum Co. v. Warren Resources of California, Inc. (2002) 103 Cal.App.4th 901, 907; Law Offices of Ian Herzog v. Law Offices of Joseph M. Fredrics (1998) 61 Cal.App.4th 672, 677.) But in connection with an alleged agreement to arbitrate, our colleagues in Division Three of this appellate district have explained: "When it is clear, both from a provision that the proposed written contract would become operative only when signed by the parties as well as from any other evidence presented by the parties that both parties contemplated that acceptance of the contract's terms would be signified by signing it, the failure to sign the agreement means no binding contract was created. [Citations.] This is so even though the party later sought to be bound by the agreement indicated a willingness to sign the agreement. [Citation.] On the other hand, if the respective parties orally agreed upon all of the terms and conditions of a proposed written agreement with the mutual intention that the oral agreement should thereupon become binding, the mere fact that a formal written agreement to the same effect has not yet been signed does not alter the binding validity of the oral agreement. [Citation.]" (Banner Entertainment, Inc. v. Superior Court (1998) 62 Cal.App.4th 348, 358, quoting Columbia Pictures, Corp. v. DeToth (1948) 87 Cal.App.2d 620, 629; accord Basura v. U.S. Home Corp. (2002) 98 Cal.App.4th 1205, 1215-1216.) As noted, this is a factual issue which we review for substantial evidence. (Laswell v. AG Seal Beach, supra, 189 Cal.App.4th at p. 1406; Banner Entertainment, Inc. v. Superior Court, supra, 62 Cal.App.4th at p. 358.)

Defendants argue plaintiffs' oral contract with Dr. Nazir contained an arbitration provision. They contend Dr. Sweidan's deposition testimony shows that plaintiffs' oral contract was pursuant to the terms of the standard written contract provided to Dr. Nazir. Because Dr. Sweidan's standard written contract contained an arbitration provision, defendants assert that the oral contract between plaintiffs and Dr. Nazir includes the arbitration provision.

But Dr. Sweidan's deposition testimony does not prove as a matter of law that plaintiffs and Dr. Nazir orally agreed to arbitrate their dispute pursuant to a written agreement. In addition, Dr. Nazir himself does not affirmatively claim that he and plaintiffs orally agreed to arbitration. Dr. Nazir testified he worked for plaintiffs under an oral agreement during June and July 2009 for coverage for other health care facilities and did not cover the hospital for them. The trial court considered Dr. Nazir's testimony and found, "[Dr.] Nazir has consistently contended that the written agreement to work for [Dr.] Sweidan at Fountain Valley hospital did not go into effect, as he revoked his acceptance of the agreement before he received an executed copy from [Dr.] Sweidan and before that agreement went into effect." Thus, substantial evidence supports the trial court's finding that no valid agreement to arbitrate exists between plaintiffs and Dr. Nazir.

IV. DISPOSITION

The order denying the renewed petition to compel arbitration is affirmed. Plaintiffs, Jacob Sweidan and Pediatrics & Neonatology Medical Group of Orange County, Inc., shall recover their costs incurred on appeal from defendants, Fountain Valley Regional Hospital, Deborah Keel, Tenet Healthcare Corp., Cotkin & Collins, Kevin A. Duffis, Dr. Veeraiah Chundu, OC Neonatal Group, Inc. and Dr. Shahid Nazir.

KRIEGLER, J., and KUMAR, J.*